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Month: October 2024

  • 9th Class Chemistry Chapter 3: Periodic Table and Periodicity of Properties

    9th Class Chapter 3: Periodic Table and Periodicity of Properties Short and Simple Question & Answer

    We know you are looking for 9th class Chemistry Chapter 3 English medium notes according to the new syllabus for 2020. That’s why we have uploaded comprehensive, easy-to-understand, and precise notes for 9th class Chemistry tailored for the Punjab board session 2020-2021. You can download these notes or view them online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q1. Define periodic table?

    Ans: The arrangement of elements in groups and periods on the basis of their similarities and properties is called periodic table.

    Q2. Define Doberiener triads?

    Ans: A German chemist doberiener observed relationship between atomic masses of several group of three elements called triads. In these groups the central or middle elements had atomic mass average of the other two elements.

    Q3. Give Example of Doberiener Triads?

    Ans: For Example, one triad group is that of calcium (40) strontium (88) and barium (137) the atomic, there was a repetition in chemical properties of every eight elements if they were arranged by the increasing atomic masses.

    Q4. Describe Drawbacks of Newland of octaves?

    Ans: Newland work could not get much recognition because There mass of strontium is the average of the atomic masses of calcium and barium

    Q5. Describe Newland of octaves?

    Ans: In 1864 British chemist Newlands put forward his observations in the form of law of octaves. Ho noted that was no space considered for undiscovered element. ii. The noble Gases were also not known at that time.

    Q6. Who was Mendeleev?

    Ans: Mendeleev (1834-1907) was a Russian chemists and inventor. He was the creator of first version of periodic table.

    Q7. Describe Mendeleev’s periodic law?

    Ans: Properties of elements are the periodic function of their atomic masses.

    Q8. Write down the Drawbacks of Mendeleev’s periodic table?

    Ans: There was following drawbacks: i. His failure to explain the position of isotopes. ii. There was wrong order of the atomic masses of some elements.

    Q9. Describe Modern periodic law?

    Ans: In 1913 H. Moseley described modern periodic law. “Properties of the elements are the periodic function of their atomic number”

    Q 10. Write down significance of atomic number?

    Ans: Atomic number is more fundamental properties then atomic masses because atomic number of every element is fixed and it is increases regularly from element to element. No two elements can have the same atomic number.

    Q 11. Why the improvement in Mendeleev’s periodic table was made?

    Ans: Because atomic number of element is more fundamental property then atomic mass in two respects. i. In increases regularly from element to element. ii. It is fixed for every element.

    Q 12. Who introduced the name of periodic table?

    Ans: In 1869 Mendeleev introduced the name of periodic

    Q 13. Why and how elements are arrange in a period?

    Ans: When the elements are arranged according to i to increasing atomic number from left to right in a horizontal row (period) properties of f elements were found repeating after regular intervals.

    Q 14. Define groups and periods?

    Ans: Groups: vertical columns present in the periodic table are called groups. It study from top to bottom. Period: Horizontal rows present in the periodic table called period. Is study from left to right.

    Q 15. Define group number and period number?

    Ans: Group Number: it tells about the number of electrons present in the outermost shell of an atom. Bns: Period Number: it tells about the number of electronic shells present in the atoms.

    Q 16. How many groups and periods present in Modern periodic Table?

    Ans: There are 18 groups and 7 periods present in the Modern periodic table.

    Q 17. How many blocks are present in Modern periodic Table?

    Ans: There are four blocks present in Modern periodic table i. S-Block ii. P-Block iii. D-Flock iv. F-flock

    Q 18. How elements are arranged into 4-Blocks?

    Ans: On the basis of completion of a particular sub shell, elements with similar sub shells, electronic configuration are referred as a block of elements.

    Q 19. Define normal or representative elements?

    Ans: Elements belong to s and p block are called normal or representative element.

    Q 20. Define transition elements.

    Ans: Those elements which belong to d and f blocks are called transition elements.

    Q 21. Who were Alchemists?

    Ans: Alchemists are groups of scientist who were trying to convert inferior metal to superior metals and trying to get secret of eternal life.

    Q 22. Write down the names of elements belonging to group-1?

    Ans: Group-1 consists of hydrogen, lithium, sodium, potassium, rubidium, cesium and francieum.

    Q 23. How the properties of elements repeat after regular intervals?

    Ans: Properties of elements repeat after regular intervals because left to right. intervals b of increasing atomic number from

    Q 24. In which pattern modern periodic table was arranged?

    Ans: Modern periodic table was arranged depends upon atomic number. The arrangement of elements based on their electronic configuration created a long form of periodic table.

    Q 25. How many elements are in first period and what are their names and symbols?

    Ans: First period contains only two elements these elements are i. Hydrogen ii. Helium

    Q 26. How many elements are placed in 4 ^ (th) period?

    Ans: There are 18 elements present in 4 ^ (th) period.

    Q 27. From which element lanthanide series starts?

    Ans: Lanthanide series is started from after lanthanum (Z = 57)

    Q 28. From which period actinide series is start?

    Ans: Actinide series is started from actinium (Z = 89)

    Q 29. Define lanthanides. In which period it belongs?

    Ans: Elements atomic no 58 to 71 are called lanthanides. It belongs to 6 ^ (th) period.

    Q 30. Define actinides in which periods in belongs?

    Ans: Elements atomic number 90 to 103 are called actinides. It belongs to 7th period.

    Q 31. How many elements present in 3rd period? Write their name and symbols?

    Ans: There are 8-elements present in 3rd period. Their names and symbols are as: i. Sodium Na ii. Magnesium Mg iii. Aluminum Al iv. Silicon Si V. Phosphorous P vi. Sulphur S vii. Chlorine CI viii. Argon Ar

    Q 32. How many periods are considered to be normal periods? Ans: First three periods considered as normal period.

    Q 33. What is the reason of arranging elements in group?

    Ans: Depending upon outermost electrons and arranged in groups. electronic configuration elements in period table are

    Q 34. What do you mean by periodic function?

    Ans: Periodic Function means properties of elements repeating after regular intervals such that elements of similar properties and similar configuration are placed in same group.

    Q 35. Why the elements are called s, p-Block elements?

    Ans: Because, the electronic configurations of elements are ends in s and p sub shells.

    Q 36. How many members are in group 17? Is there any liquid, what is its name?

    Ans: There are six elements present in 17th group. Yes, Bromine in an element which exists in liquid state.

    Q 37. Define atomic size and atomic radius?

    Ans: The half of the distance between the nuclei of the two bounded atoms is called atomic radius.

    Q 38. Write down the trends of atomic size in group and period in the periodic table?

    Ans: Group: in group atomic size of elements increases from top to bottom. Period: in any period, atomic size of elements decreases from left to right in a period.

    Q 39. Why atomic radius of elements increase down the group?

    Ans: The atomic radius increases from top to bottom in a group. Reason: because the increase of one more electronic shell in atoms of successive element which decreases the effective nuclear charge.

    Q 40. What is the reason of atomic size decreases from left to right in a period?

    Ans: In period, the atomic radii gradually decrease from left to right in periods.

    Q 41. Define ionization energy. Write down its unit?

    Ans: The ionization energy is the amount of energy required to remove the most loosely bounded electron from the valence shell of an isolate gaseous atom. Its unit is klmol¹.

    Q 42. What is the trend of ionization energy in periodic table?

    Ans: lonization energy decreasing while moves from top to bottom in any group. It increased from left to right in any period.

    Q 43. Why ionization energy decreasing from top to bottom in any group.

    Ans: lonization energy decreasing in a group due to increase in atomic size of an atom. Q 44. Why ionization energy increasing in a period? Ans: Because when we move from left to right in a period atomic size of atom decreases.

    Q 44. Define electron affinity. Write down its unit.

    Ans: The amount of energy released when an electron is added up in the outermost shell of an isolated gaseous atom. Its unit is kimol¹

    Q 45. What is the trend of electron affinity in affinity in group and period in the periodic table?

    Ans: Electron affinity decreases in the group and increases in period.

    Q 46. Why electron affinity decreases in a group?

    Ans: Electron affinity decreases in a group because of increasing atomic size of atom in a group.

    Q 47. Why electron affinity increases in a period?

    Ans: Electron affinity increases in a period because of decrease in atomic size of atom from left to right in a period.

    Q 48. What are S.I units of atomic radius?

    Ans: S.I. units of atomic radius is Pico meter and Nano meter.

    Q 49. Why the 2nd ionization energy of an element is higher than first one?

    Ans: When an electron is remove from an atom mono positive ion is formed. Mono positive ion has one more proton then electrons. Its nucleus has more influence to electrons and more energy is needed to remove second electron. This is why 2nd I.E has greater value.

    Q 50. Why the ionization energy of sodium is less than that of magnesium?

    Ans: Because both sodium and magnesium belong to same period when we move left to right in period atomic size decreases and ionization energy increases that is why sodium has low ionization energy because of greater size then magnesium.

    Q 51. Why it is difficult to remove an electron from halogens?

    Ans: Because halogen has smaller atomic size and high electron affinity and elect negative values so it is difficult to remove the electron from halogens.

    Q 52. What is shielding effect?

    Ans: The decrease in the attractive force exerted by the nucleus on the valence shell electrons due to presence of the electrons laying between the nucleus and valence shell is called shielding effect.

    Q 53. How does shielding effect decrease the forces of electrostatic attractions between and ectrosta outermost elections?

    Ans: The electron present between the nucleus and the outmost shell on an atom, reduce the nuclear charge felt by the electrons present in the outmost shell. The attraction of outmost electrons toward nucleus is partially reduced because of presence of inner electron. As a result, an atom experience less nuclear charge than that of the actual charge which is the actual c charges (Zeff).

    Q 54. Why does the bigger size of atoms have more shielding effect?

    Ans: The bigger size of atoms has more shielding effect because in bigger size atoms the number of inner shell and inner shell electrons increases hence the shielding effect of bigger size atoms also increases.

    Q 55. Why the trend of electron affinity and electronegativity does same in a period?

    Ans: The trend of electronegativity same because from left to right in period the size of an atom decreases and the attraction of the nucleus for electron also increases. It means the more nuclear force on electron and more energy is required. Therefore, electron affinity and electronegativity value also increases from left to right in a period.

    Q 56. Define electronegativity?

    Ans: The ability of an atom to attract the sheared pair of electrons toward itself in a molecule is called electronegativity.

    Q 57. Which element has the highest electronegativity?

    Ans: Fluorine has highest value of electronegativity i.e. 4.0

    Q 58. Why Noble Gases are not very reactive?

    Ans: Because, noble gases do have 2 or 8 electrons in their valence shells. It means that all the noble gases have their valance shells completely filled. Their atoms do not have vacant spaces in their valance shell to accommodate extra electrons. Therefore, noble gases do not gain, lose or share electrons. That is why noble gases are not very reactive.

    Q 59. Why cesium atomic no 55 requires little energy to release its one electron present in the outmost shell.

    Ans: Cesium requires little energy to release its outer most electrons because it has greater atomic size and low ionization energy so in cesium atom distance between nucleus and outermost shell is very large.

    Q 60. How is periodicity of properties depending upon the number of protons in an atom?

    Ans: In periodic table the atomic number increases from left to right and nuclear charge will also increase. When nuclear charge changes the properties of elements will also change.

    Q 61. What is the difference between Mendeleev’s Periodic Law and Modern Periodic Law?

    Ans: Mendeleev’s Periodic Law: Properties of elements are the periodic functions of their atomic masses.Modern Periodic Law: Properties of elements are the periodic functions of their atomic number.

    Q 62. Why and how elements are arranged in 4th period?

    Ans: The elements are arranged in 4th period because they are all having same electronic shells and elements are arranged in 4th period by increasing atomic number from left to right in a period.

    Q 63. Why shielding effect of electrons makes cation formation easy?

    Ans: The shielding effect of electron makes the cation formation easy because the electron presents between the nucleus and the outermost shell of an atom, reduce the nuclear charge felt by the electrons present in the outermost shell. The attraction of outer electron towards nucleus is partially reduced because of presence of inner electrons. As a result, as atom experiences less nuclear charge than that of the actual charge so it makes the cation formation easy.

    Download PDF Format

    The 9th class Punjab Textbook of Chemistry is an excellent starting point for your scientific journey. Besides this book, it’s beneficial to gather additional information from various online resources. This post provides you with the 9th Class Notes for Chemistry, including multiple posts for each chapter. Each chapter post contains a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Be sure to like our Facebook page for educational updates from Faiz ul Islam.

    These 9th class notes are prepared according to the syllabus of all Punjab Boards, including Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board, Sargodha Board, DG Khan Board, and Sahiwal Board.

  • 9th Class Chemistry Chapter 2: Structure of Atoms

    9th Class Chapter 2: Structure of Atoms Short and Simple Question & Answer

    We know you are looking for 9th class Chemistry Chapter 2 English medium notes according to the new syllabus for 2020. That’s why we have uploaded comprehensive, easy-to-understand, and precise notes for 9th class Chemistry tailored for the Punjab board session 2020-2021. You can download these notes or view them online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q1. What is the nature of charge on cathode rays?

    Ans: Cathode rays are negatively charged particles. J.J. Thomson discovered the e/m (change/mass) ratio of cathode rays and found it equal to electron.

    Q2. Give five characteristics of cathode rays.

    Ans: The Characteristics of cathode rays are as: i. These rays travel in straight line perpendicular to the cathode surface. ii. They can cast a sharp shadow of an opaque object if placed in their path. iii. They raise temperature of the body on which they fall. iv. J.J. Thomson discovered their e/m ratio. V. Light is produced when these rays hit the sides of the discharge tube.

    Q3. Differentiate between shell and sub-shell with example.

    Ans: Difference between Shell and Sub Shell can describe as: Shell: Each principle energy level is called Shell and these are represented by K, L, M, N Sub Shell: Each shell further contains one or more sub shells. These are represented by s, p, d, f.

    Q4. What will be the nature of charge on an atom when it loses an electron or when it gains an electron?

    Ans: When an atom loses an electron, it acquires positive charge due to more number of protons in the nucleus

    Q5. A patient has goiter, how will it be detected?

    Ans: Isotopes of iodine-131 are used for diagnosis of goiter in thyroid gland.

    Q6. Give three properties of positive rays.

    Ans: (i) They travel in straight line in a direction opposite to cathode rays. (ii) Their deflection in electric and magnetic field proved that these were positively charged. (iii) Mass of these particles was found equal to that of proton or simple multiple of it.

    Q7. What are the defects of Rutherford’s atomic model?

    Ans: It had following defects: (i) According to classical theory, electrons being the charged particles should release or emit energy continuously and they should ultimately fall into the nucleus. (ii) If the electrons emit energy continuously, they should form a continuous spectrum but in fact, line spectrum was observed.

    Q 8. As long as electron remains in an orbit; it does not emit or absorb energy. When does it emit or absorb energy? The energy is emitted or absorbed only when an electron jumps from one orbit to another. When

    Ans: an electron jumps from lower orbit to higher orbit it absorbs energy and when it jumps back from higher orbit to lower orbit, it radiates energy. This change in given by following Planck’s ” s equation.

    Q 9. Define plum pudding model. Who presented it?

    Ans: Thomson put forth his plum pudding theory. According to this theory. Atoms are solid structures of positively charge with tiny negative particles stuck inside. It is like plums in the pudding.

    Q 10. Who discovered neutrons and how?

    Ans: Chadwick discovered neutrons in 1932. He bombarded beryllium with alpha particles. He observed that highly penetrating radiations were produced. These rays were called neutrons.

    Q 11. Write three properties of neutrons.

    Ans: The properties of neutrons are as: I. Neutrons carry no charge. II. They are highly penetrating. III. Mass of neutrons are nearly equal to the mass of proton.

    Q 12. Write down the electronic configuration of Clion.

    Ans: Chlorine has 17 electrons while chloride (CI) ion has 17+1=18 electrons. Therefore, its electronic configuration will be:

    Q 13. An element has 5 electrons in M shell. Find out its atomic number.

    Ans: To have 5 electrons in M shell means its K and L shell are completely filled. Hence its electronic configuration will be

    Q 14. Define isotopes.

    Ans: Atoms of an element that have same atomic number but different atomic masses are called isotopes e.g. Hydrogen has three isotopes

    Q 15. Write use of Co-60.

    Ans: Cobalt-60 emits strongly penetrating gamma rays and hence used for cancer affecting within the body.

    Q 16. Define radioactive-isotope dating.

    Ans: The age determination of very old objects based on the half-lives of the radioactive isotope is called radioactive-isotope dating.

    Q17. What is meant by radio carbon dating or carbon dating?

    Ans: This is an important method of age determination of old carbon containing objects (fossils) by measuring the radioactivity of C-14 in them is called radio-carbon dating or simply carbon dating.

    Q18. What is Dalton’s atomic theory?

    Ans: In the beginning of 19″ century John Dalton put forward atomic theory. This theory describes that: a. All matter is made up of very small indivisible particles called atoms. b. An atom is indivisible, hard, dense sphere. c. Atoms of same element are alike. d. They combine in different ways to form compounds

    Q 19. Write contribution of J.J. Thomson.

    Ans: J.J. Thomson (1856-1940) was a British physicist. He was awarded the 1906 Noble Prize in Physics for the discovery of electron and for his work on the conduction of WN electricity in gases.

    Q 20. What is meant by plum pudding Model?

    Ans: Thomson put forth his “plum pudding” theory. He postulated that atoms were solid structures of positively charge with tiny negative particles stuck inside. It is like plums in the pudding.

    Q 21. Write contribution of Sir William crooks.

    Ans: Sir William Crooks (1832-1919) was a British chemist and physicist. He was pioneer of vacuum tubes. He worked on spectroscopy.

    Q 22. Write the contribution of Rutherford.

    Ans: Rutherford was a British-New Zealand chemist. He performed a series of experiments using alpha particles. He won the Nobel Prize in Chemistry in 1908. In 1911, he proposed the nuclear model of the atom and performed the first experiment to split the atom. Because of his great contributions, he is considered the father of nuclear science.

    Q 23. Write the contribution of Neil Bohr.

    Ans: Neil Bohr was s a Danish physicist who joined F IR Rutherford in 1912 for his post-doctoral research. In 1913, Bohr presented his atomic model based on Quantum theory. He won the 1922 Noble Prize for Physics for his work on the structure of an atom.

    Q 24. What is meant by Quantum?

    Ans: Quantum means fixed energy. It is the smallest amount of energy that can be emitted or absorbed as electromagnetic radiation. Quanta are plural of quantum.

    Q25. Write contribution of max Planck.

    Ans: In 1918 Noble prize in physics was awarded to German physicist Max Planck (1858-1947) for his work on the quantum theory

    Q 26. What is the maximum number of electrons that can be accommodated in p-subshell?

    Ans: p-subshell can accommodate maximum six electrons.

    Q 27. How many subshells are there in second shell?

    Ans: There are two subshells are present in second shell that is s and p subshells.

    Q 28. Why does an electron first fill 2p orbital and then 3s orbital?

    Ans: An electron first fill 2p orbital because the electrons fill the shells in order of their increasing energy, i.e. lower energy level is occupied first then the higher energy level. So 2p orbital as lower energy level then 3s orbital.

    Q 29. If both K and L shells of an atom are completely filled what is the total number of electrons present in them?

    Ans: There are 10 total number of electrons present in K and L shells.

    Q 30. How many electrons can be accommodated in M shell?

    Ans: M shells can accommodate maximum 18 electrons.

    Q 31. What is the electronic configuration of hydrogen atom?

    Ans: The electronic configuration of hydrogen atom is: Is¹

    Q 32. What is atomic number of phosphorus? Write down its electronic configuration.

    Ans: The atomic number of phosphorus is 15 and its electronic configuration.

    Q 33. If an element has atomic number 13 and atomic mass 27; how many electrons are there in each atom of the element?

    Ans: There are 13 electrons are present in each atom of the element.

    Q 34. How many electrons will be in M shell of an atom having atomic number 15.

    Ans: There are 5 electrons present in M shell.

    Q 35. What is maximum capacity of a shell?

    Ans: The maximum capacity of shells to accommodate the electrons is as following: K shell can accommodate 2 electrons. L shell can accommodate 8 electrons. M shell can accommodate 18 electrons. N shell can accommodate 32 electrons.

    Q 36. How was it proved that the whole mass of an atom is located at its center?

    Ans: Rutherford observed that atomic mass of the element could not explained on the basis of the masses of electron and proton only. He predicted in 1920 that some neutral particle having mass equal to that of proton must be present in an atom. He proved in his experiment that nucleus is an extremely small positively charged part. It is situated at the center of an atom it carries nearly the whole mass of an atom.

    Q 37. How was it shown that atomic nuclei are positively charged?

    Ans: Rutherford observed in his experiment, that the deflection of a few particles proved that there is a center of positive charges in an atom, which is called nucleus of an atom.

    Q 38. Name the particle which determine the mass of an atom.

    Ans: Proton and neutron are the particles which determine the mass of an atom. These are also known as nucleons.

    Q 39. What is the classical theory of radiation? How does it differ from quantum theory?

    Ans: Classical theory: According to classical theory, electrons being the charged particles should release or emit energy continuously and they should ultimately fall into the nucleus. Quantum theory: Quantum means fixed energy. It is the smallest. amount of energy that can be emitted or absorbed as electromagnetic radiation.

    Q 40. Do you know any element having no neutrons in its atoms.

    Ans: Yes, the isotope of hydrogen (Protium) has no neutron.

    Q 41. Who discovered an electron, proton and neutron? 1 neutron?

    Ans: In 1886, Goldstein discovered positively charged particles called protons. In 1897, J.J. Thomson found in an atom, the negatively charged particles known as electrons. In 1932 Chadwick discovered neutron.

    Q 42. How does electron differ from a neutron?

    Ans: Electrons: Electron is the negative charge particle. Electron is the revolving around the Nucleus. Neutrons: Neutron is the neutral particle. Neutron is present is the nucleus.

    Q 43 Explain how anode rays are formed from the gas taken in the discharge tube.

    Ans: Anode rays do not originate from the anode. In fact, these rays are produced when the cathode rays or electrons collide with the residual gas molecules present in the discharge tube and ionize them as follows: M+e^ – M ^ 2 e^ –

    Q 44. Why do the isotopes of an element have different atomic masses?

    Ans: Because the isotopes of an element have different number of neutrons

    Q 45. How many neutrons are present in C-12 and C-13?

    Ans: In C-12 there are six neutrons present and in C-13 there are seven neutrons present in the nucleus.

    Q 46. Which of the isotopes of hydrogen contains greater number of neutrons?

    Ans: Isotopes of hydrogen tritium has greater number of neutrons. It has 2 neutrons.

    Q 47. Give one example each of the use of radioactive isotope in medicine and radiotherapy.

    Ans: A radioactive isotope used in medicine is lodine-131. Radioactive Isotope used in Radiotherapy is.

    Q 48. How is the goiter in thyroid gland detected?

    Ans: Isotope of lodine-131 is used for diagnosis of goiter in the thyroid gland.

    Q 49. Define nuclear fission reaction.

    Ans: Nuclear fission is the type of nuclear reaction in which an. isotopic element is bombarded with slow moving neutrons that isotope of element emits three neutrons and split into same other isotopic elements.

    Download PDF Format

    The 9th class Punjab Textbook of Chemistry is an excellent starting point for your scientific journey. Besides this book, it’s beneficial to gather additional information from various online resources. This post provides you with the 9th Class Notes for Chemistry, including multiple posts for each chapter. Each chapter post contains a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Be sure to like our Facebook page for educational updates from Faiz ul Islam.

    These 9th class notes are prepared according to the syllabus of all Punjab Boards, including Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board, Sargodha Board, DG Khan Board, and Sahiwal Board.

  • 9th Class Chemistry Chapter 1: Fundamentals of Chemistry

    9th Class Chapter 1: Fundamentals of Chemistry Short and Simple Question & Answer

    We know you are looking for 9th class Chemistry Chapter 1 English medium notes according to the new syllabus for 2020. That’s why we have uploaded comprehensive, easy-to-understand, and precise notes for 9th class Chemistry tailored for the Punjab board session 2020-2021. You can download these notes or view them online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q1: Define Science.
    Ans: The knowledge that provides understanding of this world and how it works, is called science.
    Q2: Define industrial chemistry and analytical chemistry.
    Ans: Industrial Chemistry: The branch of chemistry that deals with the manufacture of chemical compounds on commercial scale, is called industrial chemistry. It deals with the manufacturing of fertilizers, textile, soap, agricultural products paints and paper etc.
    Analytical Chemistry: It is the branch of chemistry which deals with the separation and analysis of a sample to identify its components: The separation is carried out prior to qualitative and quantitative analysis. In this branch different techniques and instruments used for analysis are also studied.
    Q3: How can you differentiate between organic and inorganic chemistry?
    Ans: Organic Chemistry: Organic chemistry is the study of covalent compounds of carbon and hydrogen (hydrocarbons) and their derivatives
    Inorganic Chemistry: Inorganic chemistry deals with the study of all elements and their compounds except those of compounds of carbon and hydrogen (hydrocarbons) and their derivatives.
    Q4: Give the scope of bio chemistry.
    Ans: vast. Its applications are in the fields of medicines, food, science The scope of biochemistry is very vast. Its and agriculture etc.
    Q5: How does homogeneous mixture differ from heterogeneous mixture?
    Ans: Homogeneous mixture: Mixture that has uniform composition throughout are called homogeneous mixtures e.g. air Heterogeneous mixture: Heterogeneous mixture is that in which composition is not uniform throughout e.g. soil
    Q6: What is the relative atomic mass? How it is related to gram?
    Ans: The relative atomic mass of an element is the average mass of atoms of that element as compared to 1/12th the mass of one atom of carbon-12 isotope. Its unit is called atomic mass unit with symbol “amu”. One atomic mass unit is 1/12th the mass of one atom of carbon-12, When this atomic mass unit is expressed in grams, it is as 1-amu = 1.66×10-24g.
    Q7: Define empirical formula with example.
    Ans: The simplest type of formula which shows the simplest whole number ratio of atoms present in a compound is called empirical formula. For example, glucose has simplest ratio 1:2:1 of carbon, hydrogen and oxygen respectively. Hence its empirical formula is CH₂O.
    Q8: State three reasons why do you think air is a mixture and water a compound.
    Ans: The three reasons are as:
    (i) Water is a compound because it is formed by chemical combination of hydrogen and oxygen whereas air is formed by simple mixing of different gases.
    (ii) Water has fixed ratio between masses of hydrogen and oxygen, whereas in air ratio between masses of component gases is not fixed.
    (iii) Water has definite melting and boiling points whereas air does not have any fixed melting and boiling point.
    Q9: Explain why Hydrogen and Oxygen are considered as elements. Whereas water a compound?
    Ans:     Hydrogen and oxygen are elements because:
    (i) In these substances same type of atoms with same atomic number are present whereas water is made up of hydrogen and oxygen atoms having different atomic numbers.
    (ii) Hydrogen and oxygen cannot be decomposed into simpler substances by chemical means whereas water can be decomposed into hydrogen and oxygen by electrolysis.
    Q10: What is the significance of the symbol of an element?
    Ans:     Symbol is the international recognition of an element. With the help of symbols, scientists form the formula of different compounds. Symbol of clements also helps to write and understand chemical equation for different chemical reactions. The periodic table is based on symbols of different elements. We should say without symbols Chemistry would not be easy to understandable.
    Q11: State the reasons, Soft drink is a mixture whereas water is a compound?
    Ans:     Cold drink is a true solution of sugar and water in which CO2 is dissolves through pressure. We can separate these components by physical methods. It does not have definite melting and boiling point. That’s why we can say cold drink is a mixture. Whereas, water is formed by chemical combination of hydrogen and oxygen.
    Q12: Define atomic mass unit. Why is it needed?
    Ans:     The unit for relative atomic mass is called atomic mass unit. Its symbol is “amu”. One atomic mass unit is (1/12)th the mass of one atom of carbon-12″. The mass of an atom is too small to be determined practically. So, to determine the “atomic mass of various elements atomic mass unit is needed.
    Q13: Differentiate between molecular mass and formula mass. Which of the following will be molecular formula?
    Ans:     The sum of atomic masses of all the atoms presents 3 in-one molecules of a molecular mass c.g. molecular mass of water is 18 amu. The sum of atomic masses of all atoms present in one formula unit of a substance is called formula mass e.g. formula mass of sodium chloride is 58,5 amu. H₂O and H_{2}*S*O_{4} are molecular formula of molecular compounds water and Sulphuric acid respectively.
    Q14: Differentiate between homoatomic and heteroatomic molecules with examples.
    Ans:     The difference between homoatomic and heteroatomic-molecules can described as:
    Homoatomic molecules: A molecule containing same type of atoms is called homoatomic molecule. For example Hydrogen (H2), Oxygen (O2), Ozone (O3) and sulphur (Ss) are homoatomic molecules.
    Heteroatomic molecules: A molecule consisting of different type of atoms is-called heteroatomic molecule. For example NH3, H2O and CO2 are heteroatomic molecules.
    Q15: In which one of the following cases the number of hydrogen atoms is more?
    Ans    : No. of moles of hydrogen in 1 mole of HCl = 1 mole
    No. of moles of hydrogen in 2 moles of HCI = 2 moles
    Whereas;
    No. of moles of hydrogen in 1 mole of NH3 = 3 moles
    Hence 1 mole of NH3 contains 3 moles of hydrogen will have more hydrogen atoms than 2 moles of hydrogen present in 2 moles of HCl.
    Q16: What is Chemistry?
    Ans:     The branch of science which deal with the composition, structure, properties and reactions of matter is called Chemistry.
    Q17: Define Physical Chemistry.
    Ans:     The branch of f Chemistry that deals with the relationship between the composition and physical properties of matter along with the change in them is called Physical Chemistry between th
    Q18: Define Bio Chemistry.
    Ans:     It is the branch of chemistry in which we study the of substances found in living organisms. ure, composition and chemical reactions
    Q19: What is Nuclear Chemistry?
    Ans:     Nuclear Chemistry is the branch of fchemistry, which deals with the reactivity, nuclear process and fchemi properties. The main concern of this branch is with the energy of atom and its uses in daily life.
    Q20: What is Environmental Chemistry?
    Ans:     The branch of Chemistry that deals with the components of the environment and the effects of the human activities on the environment.
    Q21: What is matter? Show classification of matter.
    Ans:     Anything that has mass and occupies space is called matter. Matter can exist in any of the three physical states; solid, liquid or gas. Classification of Matter can be identify in following chart as:
    Q22: What is valency?
    Ans:     The combining capacity of an element with other elements is called valency. For example valency of carbon is 4.
    Q23: What is meant by variable valency?
    Ans:     Some elements show more than one combining power (valency) that is called variable valency. For example, in ferrous sulphate (FeS*O_{4}) the valency of iron is 2 whereas, in ferric sulphate Fe 2 (S*O_{4}) 3 the valency of iron is 3.
    Q24: What is a radical?
    Ans:     An atom or a group of atoms that have some charge and keeps in contact during a chemical reaction is called a radical e.g. Hydronium H_{3} O^ + and carbonate.CO C * O_{3} ^ – 2 during a
    Q25: What is Atomic Number and Mass Number?
    Ans:     The number of protons present in the nucleus of an atom of an element is called its atomic number.
    It is represented by symbol “Z”. For Example carbon atom has 6 protons, so its atomic number (Z) is 6. The sum of protons and neutrons present in the nucleus of an atom of an element is called mass number or nucleon number. It is represented by symbol “A”. For Example carbon atom has 6 protons and 6 neutrons, so its mass number (A) is 12.
    Q26: What is molecular formula? How molecular formula is derived from empirical formula?
    Ans:     The formula of molecular substances that shows actual number of atoms of each element present
    in a molecule of that substance is called molecular formula e.g. molecular formula of benzene is C6H6. Molecular formula is derived from empirical formula by the following relationship: Molecular formula = (Empirical formula)n Where n is 1, 2, 3 and so on, e.g. molecular formula of benzene C_{6}*H_{6} is derived from the empirical formula CH where the value of n is 6.
    Q27: What is ion? What are its types?
    Ans:     An atom or group of atoms having a charge on it is called ion. There are two types of ions i.e. cation and anion.
    i. Cation: An atom or group of atoms having positive charge on it is called cation. Cation are formed when an atom loses electrons from its outermost shell. Following equations show the formation of cations from atoms:
    ii. Anion: An atom or group of elements that has negative charge on it, is called anion. Anion is formed by the gain or addition of electrons to an atom. The following examples show the formation of an anion
    Q28: Define free radicals? How they are generated?
    Ans: Free radicals are atoms are group of atoms possessing an odd (unpaired) electron. It is represented by putting a dot over the symbols of an element. For example, H, CL, H3C. Free radicals are generated by the hemolytic (equal) breakage of the bond between two atoms when they absorb heat or light energy.
    Q29: What is Avogadro number?
    Ans:     Avogadro number is a collection of 6.02 x 1023 particles. It is represented by symbol NA. Hence, the 6.02×1023 number of atoms, molecules or formula units are called Avogadro number that is equivalent to one “Mole” of respective substance.
    Q30: Define a mole.
    Ans:     A mole is defined as the amount (mass) of a substance that contains 6. 02×1023 number of particles (atoms) molecules or formula units. It is abbreviated as “mol”. For Example, 6.02×1023 carbon
    atoms 1 mole of carbon. It can be defined as the atomic mass, molecular mass or formula mass of a substance expressed in grams is called mole. e.g., Atomic mass of carbon expressed as 12g = 1 mole of carbon.
    Q31: Write the composition of following mixtures.
    i) Air
    ii) Soil
    iii) Milk
    iv) Brass
    Ans: Air is a mixture of nitrogen, oxygen, carbon dioxide, noble gases and moisture.
    Soil: Soil is a mixture of sand, clay, mineral salts, water and air.
    Milk: Milk is a mixture of eat, water, sugar, fat, proteins, mineral salts and Vitamins.
    Brass: Brass is a mixture of copper and zinc metals.

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    The 9th class Punjab Textbook of Chemistry is an excellent starting point for your scientific journey. Besides this book, it’s beneficial to gather additional information from various online resources. This post provides you with the 9th Class Notes for Chemistry, including multiple posts for each chapter. Each chapter post contains a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Be sure to like our Facebook page for educational updates from Faiz ul Islam.

    These 9th class notes are prepared according to the syllabus of all Punjab Boards, including Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board, Sargodha Board, DG Khan Board, and Sahiwal Board.

  • 9th Class Computer Chapter 5: Designing Website

    9th Class Chapter 5: Designing Website Short and Simple Question & Answer

    We know you are looking for 9th class  computer chapter 2 English medium notes new syllabus 2020 PDF download. That’s why we upload computer notes for class 9 according to the new syllabus of Punjab board session 2020-2021. These notes are comprehensive easy to understand and precise. You can download these notes or view 9th class computer notes English medium online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q1.What is HTML?

    Ans: HTML stands for Hyper Text Markup Language. It is a formatting language used to develop web pages. HTML code can be written in any text editor like Notepad.

    Q2.Define the term hypertext?

    Ans: The term hypertext is used to refer to the special text in a webpage called hyperlinks. The hyperlinks can be clicked to move from the webpage to another.

    Q3.What is markup language?

    Ans: HTML is a markup language. It stands for hypertext markup language and is used to create webpages.

    Q4.Define HTML tag and element.

    Ans: HTML tags are the keywords that denote different elements in HTML document. The text between the start and end tags is called element.

    Q5.What are the attributes of the HTML?

    Ans: The attribute of the HTML is used to additional information about the tags. specify the working of HTML tags. They provide

    Q6.Write the types of HTML tags?

    Ans: Two types of HTML tags are paired tags and Singular tags.

    Q7.What are the basic formatting tags?

    Ans: Different formatting tags are , for bold, for italic for underline.

    Q8.Name the tag use to add image in HTML document?

    Ans: The tag to add image in tag.

    Q9.Describe the attributes of tag?

    Ans: The src attribute of this tag is used to specify the address of the image to be displayed. The border attribute is used to apply border. The width and height attribute are used to specify the width and height of the image.

    Q10.What is hyperlink?

    Ans: Hyperlink is an icon, graphic or text in a document that links to another document or object. Each website on the internet contains many tags that are linked with one another. The links are used to move from one page to another on the internet.

    Q11.Define tag and HREF?

    Ans: All hyperlinks are created with the anchor tag such as . its closing tag is . The HREF attribute of is used to specify the link destination such as

    Download PDF Format

    he class 9 Punjab Textbook of Computer Science is commonly considered the beginning of your technological journey. Besides this book, which is an excellent source for newbies, I would recommend you summarize the others information online. Moreover, This post presents you with the 9th Class Notes for Computer Science. It contains five posts against each chapter. In addition, Chapter posts contain a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Like Our Facebook Page For Educational Updates faizulislam

    These 9th class notes prepared according to the syllabus of all Punjab Boards. Other boards other than Punjab do not follow class 9 computer science notes. These Punjab boards are Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board Sargodha Board, DG Khan Board, Sahiwal Board.

  • 9th Class Computer Chapter 2: Binary System

    9th Class Chapter 2: Binary System Short and Simple Question & Answer

    We know you are looking for 9th class  computer chapter 2 English medium notes new syllabus 2020 PDF download. That’s why we upload computer notes for class 9 according to the new syllabus of Punjab board session 2020-2021. These notes are comprehensive easy to understand and precise. You can download these notes or view 9th class computer notes English medium online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q. 1. What is number system?

    Ans: A set of values used to represent different quantities is known as number system. For example. a number system can be used to represent the number of students in a class.

    Q.2. What is machine language?

    Ans: A computer understands the language of 1s and Os only called machine language.

    Q.3. How does digital computer represent data?

    Ans: The digital computer represents all types of data in binary numbers. It includes audio. graphics. video, text, and numbers.

    Q.4. What do you mean by the base or radix of a number system?

    Ans: The number of digits used in any’ number system defines its base or radix. For example. base of decimal systems is 10 because it uses digits 0 to 9. Similarly, the base of binary system is 2. because it uses digits 0 and 1.

    Q.5. List three types of number systems?

    Ans: Three types of number systems are decimal number system, binary number system and hexadecimal number system.

    Q.6. What is the most common number system?

    Ans: Decimal number system is commonly used in our daily life. Its base is 10 and it consists of ten digits from Oto 9. These digits ca be used to represent any numeric value.

    Q.7. What is binary number system?

    Ans: Binary number system consists of two digits O and I and Its base is 2. Each digit or bit in binary number system can be 0 or 1. The position of each digit in binary number system- represents a power of base 2.

    Q.8. What is hexadecimal number system?

    Ans: Hexadecimal number system consists of 16 digits from 0 to 9 and A to F. The alphabets A to F represent decimal numbers from 10 to 15. The base of this number system is 16.

    Q.9. Define computer memory and writes its types.

    Ans: Computer memory is a physical device that can store data. The two types of computer memory are volatile memory and non-volatile memory.

    Q.10. What is volatile memory? Give an example.

    Ans: Volatile memory is a device that can store data as long as the power supply is connected to it. The contents of volatile memory are lost as the power supply is disconnected. Random Access Memory (RAM) is an example of volatile memory.

    Q.11. What is non-volatile memory? Given examples.

    Ans: Non-volatile memory is a device that stores data even if the power supply is not connected.
    to it. Hard drive, flash drive and memory cards are examples of non-volatile memory. It is also
    known as secondary storage.9th Class

    Q.12. Write three differences between memory and storage.

    Ans: Memory stores data temporarily but storage stores it permanently. Memory has high speed than storage. The capacity of memory is typically smaller than storage.

    Q.13. How is data represented in computer?

    Ans: The digital computers store data in binary form. Different types of data such as .text, picture, video, or applications are stored in the form of Os and 1s. All characters on the keyboard are associated with the codes known as ASCII code. It is a standard used to represent data in computer memory.

    Q.14. What Is ASCII?

    Ans: ASCII stands for American Standard Code for Information Interchange. It is a standard used to represent data in computer memory.

    Q.15. Write ASCII codes for any three characters.

    Ans: The ASCII code for 1 is 49. The ASCII code for + is 43. The ASCII code for@ is 64.

    Q.16. What is the use of storage devices?

    Ans: Storage devices ore used to store data and programs permanently. These devices are. nonvolatile and retain the contents even if the power is turned off.

    Q.17. Give some examples of storage devices.

    Ans: Some examples of commonly used secondary storage devices are hard disks, optical discs (CDs/DVDs), USB flash drives and memory cards.

    Q.18. What is Boolean algebra?

    Ans: Boolean algebra is the algebra of logic. It uses binary values, so it is also known as binary- algebra or logical algebra. Boolean algebra is used in the designing of logic circuits in computer. These circuits perform different logical operations.

    Q.19. What is Boolean proposition? Give example.

    Ans: A Boolean proposition is a sentence that can be true or false. For example. the sentence “Are you a student?” is a proposition because its result is true or false. However, the sentence “What is your address?” is not a proposition because its result is not in the form of true or false.

    Q.20. What do you mean by truth value?

    Ans: The possible value of true or false that can be given to a Boolean proposition is known as truth values. It Is given on the basis of truthfulness or falsity 9f the Boolean proposition.

    Q.21. What are logical operators? Write three names of logical operators.

    Ans: Logical operators are used to combine more than one Boolean proposition or negate a proposition. Three logical operators include AND, OR and NOT.

    Q.22. Define compound Boolean proposition?

    Ans: The Boolean proposition that consists of multiple propositions is known as compound
    Boolean proposition.

    Q.23. Define logical expression?

    Ans: Logical expression is an expression in which some logical operator is applied to the Boolean
    proposition. The result of logical expression Is true or false. The logical expression is also
    known as Boolean expression.

    Q.24. What is the use of AND operator?

    Ans: The AND operator is used to connect two or more propositions. The compound Boolean proposition is true if all connected propositions are true. Its result is false result if any proposition is false. It can be denoted by a dot (.).

    Q.25. What Is the use of OR operator?

    Ans: The OR operator is used to connect two or more propositions. The compound Boolean proposition is true if any connected proposition is true. Its result is false result if all propositions are fals. It can be denoted by a plus (+).

    Q.26. W at Is the use of NOT operator?

    Ans: The NOT operator is used to negate a proposition; it reverses the result of a proposition. For example, if P = “Today is Friday” is true then NOT(P) will be false. It can be denoted by negation symbol(-).

    Q.27. What Is truth table?

    Ans: A truth table is used to check whether a proposition is true or false. It is typically used to check the truth value of a proposition in which logical operators are used.

    Q.28. What is commutative law of Boolean algebra?

    Ans: The commutative law states that the order of application of two separate propositions is not important. It means that the order in which two variables in a Boolean expression are calculated does not change its result.

    Q.29. What Is distributive law of Boolean algebra?

    Ans: The distributive law is the most important law in Boolean algebra. It involves in two operators AND and OR.

    Q.30. What Is identity law of Boolean algebra?

    Ans: The identity law works with two operators AND and OR. It states that a variable OR’ed with 0 False) is always equal to that variable. Similarly, a variable. AND’ed with 1 (True) is always equal to that variable.

    Download PDF Format

    he class 9 Punjab Textbook of Computer Science is commonly considered the beginning of your technological journey. Besides this book, which is an excellent source for newbies, I would recommend you summarize the others information online. Moreover, This post presents you with the 9th Class Notes for Computer Science. It contains five posts against each chapter. In addition, Chapter posts contain a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Like Our Facebook Page For Educational Updates faizulislam

    These 9th class notes prepared according to the syllabus of all Punjab Boards. Other boards other than Punjab do not follow class 9 computer science notes. These Punjab boards are Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board Sargodha Board, DG Khan Board, Sahiwal Board.

  • 9th Class Computer Chapter 3: Networks

    9th Class Chapter 3: Networks Short and Simple Question & Answer

    We know you are looking for 9th class  computer chapter 2 English medium notes new syllabus 2020 PDF download. That’s why we upload computer notes for class 9 according to the new syllabus of Punjab board session 2020-2021. These notes are comprehensive easy to understand and precise. You can download these notes or view 9th class computer notes English medium online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q.1. What is computer network?

    Ans: A computer network consists of computers and devices connected to share information and resources. The resources may include printers, hard disks, scanners, or programs etc.

    Q.2. How are computers connected in computer network?

    Ans: The computers in the network are connected through communication media such as physical cable or a wireless connection. The communication medium is also known as communication channel.
    Q.3. List any five uses of computer network?

    Ans: Five uses of computer network include sending / receiving emails, playing online games, watching videos, reading newspaper, and studying online.

    Q.4. Give an example of sharing a file using a computer network.

    Ans: Computer network can be used to share files. For example, the education board can share the date sheet file with all students. The students can access it over the Internet.

    Q.5. What is video conferencing?

    Ans: Video conferencing is a popular method of communication. A video conference uses computers, video cameras, microphones, and networking technologies to conduct face- to face meetings over the Internet.

    Q.6. How can a computer network help to Increase storage capacity?

    Ans: Computer network can be used to increase the storage capacity. The users do. not need to store everything on personal computer. They can store and access the files remotely on the computer with higher storage capacity.

    Q.7. Write two examples of remote storage service.

    Ans: The popular services for remote storage are OneDrive, DropBox and Google Drive.

    Q.8. Why server is more powerful than clients?

    Ans: Server provides services to client computers. It performs more activities than clients such as processing data, controlling access, and sharing software etc. That is why the server is more powerful than clients.

    Q.9. What are different types of dedicated servers?

    Ans: Different types of dedicated servers include file server, print server, database server and web server. A dedicated server is used to perform a specific task. For example, file server is used to store and manage files. Print server is used to manage printers and print jobs.

    Q.10. What is client?

    Ans: The client is a computer in the network that is connected with a server to access different resources. It sends request to the server for resources. The client is typically less powerful than server.

    Q.11. How do the client and server communicate with each other?

    Ans: The client and server communicate with each other over the network. The client sends request to the server for resources. The server provides the requested resource to client.

    Q.12. What is a client application?

    Ans: A client application isthe software that is used to send a request from client to server. It provides an interface to transfer the request to the server. Web browser is an example of a client application.

    Q.13. What is point-to-point connection?

    Ans: A point-to-point connection refers to the direct link between a sender and a receiver.. Both devices a connected with one connection line. The connection between a TV and the remote control is an example of point-to-point connection.

    Q.14. What is multipoint connection?

    Ans: A multipoint connection refers to the link between one sender and multiple receivers. A single link can be shared by more devices. Wi-Fi based network is an example of multipoint connection. This connection is shared among multiple devices.

    Q.15. What is network topology?

    Ans: A network can be arranged in different ways. Th physical layout or arrangement of connected devices in a network is called network topology. It is the shape of a network.

    Q.16. List different types of network topologies?

    Ans: Different network topologies include bus topology, ring topology, star topology, tree topology and mesh topology.

    Q.17. What la bus topology?

    Ans: Bus topology is the simplest type of network. It supports a small number of computers. In bus. topology, all computers or network nodes are connected to a common communication medium. This medium is known as bus or backbone.

    Q.18. Why are terminators used in bus topology?

    Ans: When the signal reaches the end of the wire. it bounces back and travel up to the wire. Terminator is added at the ends of the central wire to prevent bouncing of signals.

    Q.19. What happens if a bus topology has too many computers?

    Ans: Computer network can be used to share files. For example, the education board can share the date sheet file with all students. The students can access it over the Internet.

    Q.20. Write any three advantage of bus topology?

    Ans: It is simple and easy to use. It requires small length of cable to connect computers. It is less expensive.

    Q.21. How does star topology work?

    Ans: All computers in star topology are connected with a central device called hub or switch. The sending computer sends the data to central device. The central device sends data to the receiving computer. Each computer in star network communicates with a central
    device. If central device fails, the whole network becomes useless.

    Q.22. Give any three features of star topology?

    Ans: Star topology is suitable both for small and large networks. It is easy to maintain and modify. It is more flexible than other topologies.

    Q.23. Why star topology is more reliable than bus or ring topology?

    Ans: Star topology is more reliable than bus or ring topology. It allows the user to remove or add a device without affecting the network. It is easier to troubleshoot than other topologies. If one computer foils, it does not affect the other computers in the network.

    Q.24. What is ring topology?

    Ans: In ring topology, each computer is connected to the next computer with the last one connected to the first. A ring con be unidirectional or bidirectional. In a unidirectional ring, data can be sent in one direction. In a bidirectional ring. data can travel in any direction.

    Q.25. What Is mesh topology?

    Ans: In a mesh topology. every device in the network is physically connected to every other device in the network. A message can be sent on different possible paths from source to destination. Mesh topology provides improved performance and reliability.

    Q.26. What is data communication?

    Ans: Data communication is the exchange of messages between sending and receiving devices through a communication medium. The messages are the information that may be in the form of text, numbers, images, audio, and video.

    Q.27. List different components of data communication?

    Ans: Different components of data communication system are sender, receiver, message, protocol, and transmission medium.

    Q.28. What is sender in data communication?

    Ans: Sender is a device that sends the message. It initiates communication process. It is also called source or transmitter. A computer is normally used as sender in data communication.

    Q.29. What is receiver in data communication?

    Ans: Receiver is a device that receives the message. It is also called sink. The receiver must be capable of accepting a message. The receiver can be computer, printer or another computer related device.

    Q.30. What is message in data communication?

    Ans: The message is the data, information, or instruction to be communicated. It may consist of text, number, picture, audio, video, or a combination of these.

    Q.31. What do you mean by protocol?

    Ans: A protocol is a set of rules that governs data communication. It is a formal agreement between communication devices to send and receive information. The devices cannot communicate without protocol.

    Q.32. How Is the sender and receiver connected in data communication?

    Ans: Medium is the path that connects sender and receiver. It is used to transmit data. It.is
    also called communication channel.

    Q.33. What are different types of transmission medium?

    Ans: The transmission medium can be wired or wireless. The wired transmission media are twisted pair cable, coaxial cable, and fiber optic cable. The wireless transmission media include radio waves, microwaves, and satellites etc.

    Q.34. What are two parts of a message in data communication?

    Ans: The message in data communication is sent in the form of packets. Each message consists of two parts called payload and control information.

    Q.35. What is payload?

    Ans: Payload is the actual contents of the message. Suppose a user writes an email message to a friend. The content of the email message is the payload.

    Q.36. What is the use of control information in data communication?

    Ans: Control information contains the information about the sender and the receiver. The control information is used to deliver the message to the receiver properly. The message cannot be delivered if the control information is wrong or missing.

    Q.37. What Is TCP/IP model?

    Ans: TCP/IP stands for Transmission Control Protocol / Internet Protocol. TCP/IP is a network. model that is used to transfer data from one computer to another over the Internet and other networks.

    Q.38. List the five layers of the TCP/IP model?

    Ans: The five layers of TCP/IP Models are: (i) Application Layer (ii) Transport Layer (iii) Network Layer (iv) Data Link Layer (v) Physical Layer

    Q.39. What Is use of application layer in TCP/IP model?

    Ans: The application layer provides an interface between network services and application programs. Many protocols are used at this layer to perform various functions. These protocols form the basics of various network services such as user login, file transfer, web surfing etc.

    Q.40. What is use of transport layer in TCP/IP model?

    Ans: The transport layer provides the mechanism to transport data between network devices. It controls the flow of data. It ensures that messages are delivered without any error. The transport layer also provides the acknowledgement of successful data transmission.

    Q.41. List three protocols used at application layer.

    Ans: Three protocols used at application layer include FTP, HTTP and SMTP.

    Q.42. What Is use of network layer in TCP/IP model?

    Ans: The network layer manages the delivery of data from source to destination across different networks. The network layer finds the best physical path for the data to reach its destination.

    Q.43. Give an example of the protocol used at network layer?

    Ans: An example of the protocol used at network layer is Internet Protocol (IP).

    Q.44. What Is use of data link layer in TCP/IP model?

    Ans: The data link layer manages the transfer of data between the devices on the same
    network. It also manages the flow and error control of data. It detects and retransmits
    faulty data.

    Q.45. Give an example of the protocol used at data link layer?

    Ans: An example of the protocol used at data link layer is Ethernet.

    Q.46. What is use of physical layer in TCP/IP model?

    Ans: The physical layer Is the bottom layer of TCP/IP model. This layer is about the physical medium used in communication like cabling. It defines the data transmission rate in terms of number of bits sent per second.

    Q.47. What Is use of FTP?

    Ans: File Transfer Protocol (FTP) Is a standard TCP/IP protocol that is used to transfer files from one computer to another. It is a client-server protocol where the client requests for a file and the server provides it.

    Q.48. What Is use of HTTP?

    Ans: Hypertext Transfer Protocol (HTTP) is a protocol that is used by World Wide Web (WWW) to transfer webpages between a client and a web server. A web server is also known as HTTP server.

    Q.49. What Is use of SMTP?

    Ans: Simple Mail Transfer Protocol (SMTP) is a protocol that is used to send and receive emails. It is very popular protocol for email communication.

    Q.50. What Is use of address in data communication?

    Ans: An address in data communication is used to uniquely identify a device on the network. It is also known as IP address where IP stands for Internet Protocol. Different devices over a network communicate with each other using their unique addresses.

    Q.51. List two types of IP addressing schemes?

    Ans: Two types of IP addressing schemes are IPv4 and IPv6.

    Q.52. What are the sizes of IPv4 and IPv6?

    Ans: IPv4 is a 32-bits (232) in size. It provides approximately 4.3 billion addresses. IPv6 is a 128-bits (2128) in size. It provides approximately 3.4×1038 IP addresses.

    Q.53. What la IPV4?

    Ans: IPv4 is a 32-bits (232) in size. The 32 bits are divided into four parts known as octet. One octet is equal to 8 bits. The four octets are separated by dot. Each octet in the IP address is written in decimal format. Each octet can contain a decimal value from Oto 255.

    Q.54. Give an example of IPY4 IP address?

    Ans: An example of an IPv4 address is 10.10.20.1.

    Q.55. What Is IPV6?

    Ans: IPv6 is a 128-bits (2128) in size. It provides a large number of IP addresses (2128). It is 7.9 x 1028 times more than the number of addresses in IPv4. IPv6 is written in hexadecimal. It has eight
    groups separated by colon (:). Each group has four hexadecimal digits.

    Q.56. Why is IPY6 needed?

    Ans: Many devices are connecting to the Internet. it was a concern that IPv4 may not be enough for all these devices. IPv6 was introduced as a solution for expanding the possible number of users on the Internet.

    Q.57. Give an example of IPY6 IP address?

    Ans: An example of IPv6 address is 2DAB:FFFF:0000:3EAE:OI AA:00FF:DD72:2C4A

    Q.58. Differentiate between IPv4 and IPv6?

    Ans: 1Pv4 is a 32-bits (232) in size but IPv6 is a 128-bits (2128) in size. 1Pv4 provides approximately 4.3 billion addresses whereas IPv6 provides approximately 3.4×1038 addresses. IPv4 is divided into four groups separated with dot. IPv6 is divided into eight groups separated with colon.

    Q.59. What is a router?

    Ans: Router is a networking device that connects multiple networks. It can transmit data from one network to another network in less time. It manages the best route between any two communication networks. it can be used on a network of any size.

    Q.60. How does a router forward a packet?

    Ans: A router analyses the destination IP address of the incoming data packet. it determines the best route to forward the packet. It then sends the packet to that route. A router is usually placed at the meeting point of two or more networks.

    Q.61. How does routing process work in networking?

    Ans: Routing is a process of transferring data from the device on one network to the device on another network. Every data packet has two addresses. The source address identifies the device that sends data. The destination address identifies the device that receives data.

    Download PDF Format

    he class 9 Punjab Textbook of Computer Science is commonly considered the beginning of your technological journey. Besides this book, which is an excellent source for newbies, I would recommend you summarize the others information online. Moreover, This post presents you with the 9th Class Notes for Computer Science. It contains five posts against each chapter. In addition, Chapter posts contain a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Like Our Facebook Page For Educational Updates faizulislam

    These 9th class notes prepared according to the syllabus of all Punjab Boards. Other boards other than Punjab do not follow class 9 computer science notes. These Punjab boards are Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board Sargodha Board, DG Khan Board, Sahiwal Board.

  • 9th Class Computer Chapter 4: Data and Privacy

    9th Class Chapter 4: Data and Privacy Short and Simple Question & Answer

    We know you are looking for 9th class  computer chapter 2 English medium notes new syllabus 2020 PDF download. That’s why we upload computer notes for class 9 according to the new syllabus of Punjab board session 2020-2021. These notes are comprehensive easy to understand and precise. You can download these notes or view 9th class computer notes English medium online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q.1. What are computer ethics?

    Ans: Computer ethics are the moral rules and guidelines that determine the proper use of computer system. The computer should be used according to the ethics in order to avoid any problem in the society.

    Q.2. List any five Issues related to data security.

    Ans: Five issues related to data security are confidentiality & privacy, piracy, patent, copyright and trade secrets.

    Q.3. Define confidentiality.

    Ans: Confidentiality is the responsibility to keep other’s personal information private. It is a matter of taking care of other people.

    Q.4. What is data privacy?

    Ans: Data privacy refers io the right of an individual or an organization to keep personal information private. It is typically related to the personal information stored on the computer.

    Q.5. Why has confidentiality and privacy become critical?

    Ans: The privacy and confidentiality have become very critical due to the use of computers and the Internet. The potential threat to the personal data includes the improper use of computerized dale.

    Q.6. What Is meant by piracy?

    Ans: Piracy refers to the process of making illegal copies of any work protected by the copyright law. It can be book, software, song, movie, poetry, painting, or house design etc.

    Q.7. Differentiate between authorized and unauthorized access.

    Ans: The process of accessing a computer system and its resources legally is called authorized access the process of accessing a computer system and its resources illegally is called unauthorized access.

    Q.8. What do you mean by software piracy?

    Ans: Software piracy is the illegal copying, distribution or use of copyright software. Most licensed software can only be used by one user on one computer. The user can copy the software tor backup but it is illegal to use it on different computer.

    Q.9. What type of software Is available at no cost?

    Ans: 0 The open-source software is available at no cost. Anyone can modify the source code and redistribute it.

    Q.10. What is key?

    Ans: The software companies sell software along with a confidential text called key. The software can be activated using the key. The key is only given to the users who legally buy the software.

    Q.11. Define cracking.

    Ans: Some people try to get software key using illegal means This process is known as cracking.

    Q.12. List five types of software piracy.

    Ans: Five types of software piracy are soft lifting, client-server overuse, hard disk loading, counterfeiting and online piracy.

    Q.13. What is soft lifting?

    Ans: soft lifting is a process of borrowing a software application from a colleague and installing it on your device.

    Q.14. What Is client server overuse?

    Ans: Client-server overuse is a process of installing more copies of the software than number of licenses. It is typically done in client-server network.

    Q.15. What Is hard disk loading?

    Ans: Hard disk loading Is a process of installing and selling unauthorized copies of the software on new or refurbished computers.

    Q.16. What is counterfeiting?

    Ans: Counterfeiting is a process of selling the duplicate copies of the software.

    Q.17. What Is meant by online piracy?

    Ans: Online piracy Is a process of downloading the Illegal copies of software.

    Q.18. How are computers used for fraud and misuse?

    Ans: Fraud and misuse refer to the unauthorized activities. The computers and the Internet are frequently used to perform such activities. It includes theft of money by electronic means. theft of services and theft of valuable data..

    Q.19. What is patent?

    Ans: A patent is a right that is granted to the owner for a certain period of time. It is effective way to protect the idea. It can be for any invention such as device substance, method, or process. Any other person or organization cannot copy that idea for a certain period.

    Q.20. Why Is It Important to register a patent?

    Ans: It Is important to register a patent If someone is doing research in any field and has a new idea. It stops other people to make or sell anything on the basis of that idea. The owner of the Idea can exclusively use the idea to make and sell anything.

    Q.21. What do you mean by copyright?

    Ans: A copyright is a type of legal protection that protects some Idea or product from being copied. It is illegal to use any copyrighted material such as book, software, picture, video, or music. The copyright symbol is usually used with copyrighted material.

    Q.22. What Is meant by trade secrets?

    Ans: Trade secrets refer to the secret information of a company that play Important role for Its success. They have a lot of value and importance for the company. They provide the company an advantage over the other companies.

    Q.23. Why Is It Important to protect trade secrets?

    Ans: The trade secrets must be protected carefully. It ensures that the company has a competitive advantage over others. The unauthorized use of trade secrets can harm the company.

    Q.24. What is sabotage?

    Ans: Sabotage is a serious attack on a computer system. A malicious user can attack the computer system remotely over the network. The attacker may include virus with some. free software. It may change or destroy information and sabotage important data on the system.

    Q.25. Give five examples of the organizations that store data of the people in computers?

    Ans: Five examples of these organizations are hospitals, NADRA, schools, Board of Intermediate and Secondary Education, and passport offices.

    Q.26. What is meant by data brokers?

    Ans: There are many companies that collect. buy and sell the consumer Information. These companies are known as data brokers. They use this information to know the interests of the people.

    Q.27. What are cookies?

    Ans: A lot of Information is generated when the user browses the Internet. This information is usually stored with the Web surfer known as cookies. The cookies can track the interests of the people when they visit different websites.9th Class

    Q.28. Define encryption?

    Ans: Encryption is the process of encoding plain data into unreadable format.

    Q.29. What is ciphertext?

    Ans: The unreadable format of data is called ciphertext. It is performed in encryption.

    Q.30. Define decryption?

    Ans: The process of converting ciphertext bock to plain text is called decryption.

    Q.31. How is the encrypted data converted into plain data?

    Ans: A secret code is required to convert the encrypted data into plain data in order to read it. The secret code is called key and Is just like a password.

    Q.32. Why is encryption performed?

    Ans: The encryption is performed to ensure that only authorized persons can read the data. It is an important method of providing data security. It ensures protection from hackers and privacy. The data is protected when transferred across devices.

    Q.33. What is substitution cipher method?

    Ans: Substitution cipher method is a method of encryption in which the characters of original text are replaced with some other characters. The substitution is done by a fixed predefined system. Two types of substitution cipher methods are Caesar cipher and Vigenère cipher.

    Q.34. What Is Caesar cipher method?

    Ans: Caesar cipher method replaces each alphabet in the plain text with another alphabet. Each alphabet is replaced with the alphabet that is at a fixed number of positions to the left or right of original alphabet.

    Q.35. Who was Caesar?

    Ans: Caesar was a Roman politician and military general. He was born in July 13, 100
    BC. Rome. Italy. He played an important role in the rise of Roman Empire. He was killed on March 15 44BC.

    Q.36. Write any two quotes of was Caesar?

    Ans: Experience is the teacher of all things. Men freely believe that which they desire.

    Q.37. What is Vigenère cipher method?

    Ans: Vigenère cipher method uses a table known as Vigenère Cipher table. The Vigenère cipher method works with substitution key. The key is combined with the plaintext to generate the ciphertext.

    Q.38. What is Vigenère cipher table?9th Class

    Ans: The Vigenère cipher table consists of 26 rows and 26 columns. The first row contains the original alphabets from A to Z. The alphabet is shifted one letter to the left in each subsequent row. The rows and columns are labeled by alphabets from A to Z.

    Q.39. What Is meant by Interim cipher?

    Ans: In some cases, the key in Vigenère method may have less number of cases than the plaintext. The letters from the beginning of the plaintext are used to make the length of the key same as the plaintext. It Is known as interim ciphertext.

    Q.40. What is Vigenère cipher widget?

    Ans: The Vigenère cipher widget shows animation of the encryption and decryption of plaintext. It uses Vigenère cipher method according to the given key.

    Q.41. What Is random substitution method?

    Ans: The messages encrypted with Caesar cipher method are easy to crack. This method can be modified by shifting the letter to a random letter. This IS called random substitution cipher method.

    Q.42. What do you know about frequency analysis?

    Ans: The frequency analysis is the study of the frequency of letters or group of letters in a ciphertext. This method is used as an aid to break the.

    Q.43. What is the purpose of password?

    Ans: The purpose of password is to protect data stored on a computer. It protects data from being lost. misused or deleted by any person. The system can be accessed by a person who knows the password. Password can be changed only by authorized person.

    Q.44. Write any three characteristics of a good password.

    Ans: A good password consists of at least eight characters. it does not contaln username, real name. children name or company name. It is different om previous passwords.

    Q.45. Differentiate between cryptographic key and password.

    Ans: The cryptographic key is used to read an encrypted message whereas password Is used for authentication to enter system whereas. A key is not same as the password in computer security, but a password can be used as a key. A password is generated, read, remembered, and reproduced by humans but a key is used by software or humans to process a message.

    Q.46. What Is CAPTCHA?9th Class

    Ans: CAPTCHA is a set of random letters and numbers that appear as a distorted image and a textbox. The user needs to type the characters In the Image Into the textbox to gain access to the system. CAPTCHA text is only readable by humans not the computer.

    Q.47. What Is cybercrime?

    Ans: A cybercrime is a criminal activity carried out by means of computers and the internet. In some cybercrimes, the computer is used to commit a crime such as fraud, kidnapping, murder and stealing money from bank account or credit card.

    Q.48. How do the criminal access personal information?

    Ans: The criminals use Internet to access the personal information such as username, password, and credit card number.

    Q.49. List any three types of cybercrime.

    Ans: Three types of cybercrimes are identity theft, transection fraud, DoS attack, and hacking.

    Q.50. What Is identity theft?

    Ans: The identity theft is a criminal activity in which the hacker traps someone to give the account details and password. The hacker can then use the account of the user to perform any malicious activities.

    Q.51. How does transaction fraud occur?

    Ans: The transaction fraud is a criminal activity in which the scammer performs an illegal transaction. For example, the scammer offers an item for online. Someone buys the items and makes the payment, but the scammer never delivers the item.

    Q.52. How does advance fee fraud occur?

    Ans: The advance fee fraud is a criminal activity in which the criminal informs the user that he has won a prize or lottery. He then asks the user to submit a processing fee so the prize may be dispatched. It is very common type of cybercrime in which people lose the money.

    Q.53. What is hacking and hacker?

    Ans: An act of unauthorized access to the computer or network is called hacking. The person who gains unauthorized access to the computer system is called hacker. The hackers are computer experts and use their knowledge to break into the computer system and network.

    Q.54. When does hacking usually happen?

    Ans: Hacking usually happens when user downloads a file from the Internet and executes It. The software connects hacker to the computer. The hackers typically access the information for financial benefits such as stealing money from bank account or using credit card.

    Q.55. What is spyware?

    Ans: Spyware is a type of software that is used in hacking. It connects the hacker to the computer to access important Information without user knowledge. It runs in the background and collects information such as bank details and passwords.

    Q.56. What is National Response Centre against cybercrime?

    Ans: The National Response Centre for cybercrime is a law enforcement agency of Pakistan. It is dedicated to fight cybercrimes; it is working under Federal9.

    Q.57. What is phishi (BA), Its website is www.nr3c.gov.ph Is attack?

    Ans: A phishing attack is a criminal activity in which the criminal uses fake email and website to get sensitive information such as username. password and credit card details.

    Q.58. What is meant by denial of service?

    Ans: A Denial of Service (DoS) is a cyber-attack that makes a machine or network resource unavailable. The attack makes the resource too busy by sending many requests for it. The actual user cannot get it. It sometimes overloads system so much that network is shut down.

    Download PDF Format

    he class 9 Punjab Textbook of Computer Science is commonly considered the beginning of your technological journey. Besides this book, which is an excellent source for newbies, I would recommend you summarize the others information online. Moreover, This post presents you with the 9th Class Notes for Computer Science. It contains five posts against each chapter. In addition, Chapter posts contain a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Like Our Facebook Page For Educational Updates faizulislam

    These 9th class notes prepared according to the syllabus of all Punjab Boards. Other boards other than Punjab do not follow class 9 computer science notes. These Punjab boards are Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board Sargodha Board, DG Khan Board, Sahiwal Board.

  • 9th Class Computer Chapter 1: Problem-Solving

    9th Class Chapter 1: Problem-Solving Short and Simple Question & Answer

    We know you are looking for 9th class  computer chapter 1 English medium notes new syllabus 2020 PDF download. That’s why we upload computer notes for class 9 according to the new syllabus of Punjab board session 2020-2021. These notes are comprehensive easy to understand and precise. You can download these notes or view 9th class computer notes English medium online. Many students practice 2024 Biology important questions by FAIZ UL ISLAM and get good marks in the exam.

    Q.1. Define problem?

    Ans: A problem is a situation or matter that requires proper attention to be resolved.

    Q.2. What Is a problem statement?

    Ans: A problem statement is a brief description of the problem to be solved. It describes the problem and identifies its causes and solutions. The problem statement must be prepared before finding the solution to the problem.

    Q.3. What Is problem-solving?

    Ans: Problem solving is a process of identifying a problem and finding its best solution. Problem-solving is a thinking process. It is a skill that can be developed by following a well-organized approach.

    Q.4. Write the names of steps that are Involved In problem-solving?

    Ans: The steps involved in problem-solving are defining the problem, analyzing the problem, planning the solution, candid solutions, and selecting the best solution.

    Q.5. Why is it important to define a problem?

    Ans: A problem cannot be solved if it is not defined correctly. The clearly defined problem helps the user to find the solution.

    Q.6. List three strategies to define a problem?

    Ans: Three strategies to define a problem include gaining back knowledge, using guesses, and drawing a picture.

    Q. 7. Why is It important to gain background knowledge of a problem?

    Ans: It is important to understand the situation and circumstances in which the problem occurs. It allows the user to understand the given state. It also helps to know what the solution will look like and how to measure the solution.

    Q.8. What Is problem analysis? Why Is It Important?

    Ans: Problem analysis is a process of understanding the given problem. It is very important to understand a problem before trying to solve it. A clear understanding of a problem helps the user to solve it correctly and easily. It also saves money, time, and resources.

    Q.9. List five Ws to understand a problem?

    Ans: The five Ws to understand a problem are What, Who, Why, When, and Where.

    Q.10. What happens In the phase of planning the solution to a problem?

    Ans: The solution to a problem is planned after defining and analyzing the problem. The problem is assessed to find the right strategy to solve the problem. This phase specifies the actions required to solve the problem. It also specifies the resources required for the solution.

    Q. 11. State different strategies to plan the solution of a problem?

    Ans: Different strategies to plan the solution of a problem include divide and conquer; guess, check and improve; and act it out.

    Q. 12. Which strategy divides a complex problem into smaller problems and why?

    Ans: The divide and conquer strategy divides a complex problem into smaller problems. The smaller problems can be solved separately. The process of solving the problem becomes easier. It also reduces the complexity of the solution.

    Q: 13. What Is a candid solution to a problem?

    Ans: The word candid means something unplanned. The candid solution is typically found using guessing without detailed planning. It saves a lot of time but may not be the actual solution to the problem.

    Q. 14. What is a flowchart?

    Ans: A flowchart is a graphical representation of the solution of a problem. Standard symbols are used to represent different steps of the solution. Different symbols are used in flowcharts to represent different operations.

    Q. 15. Write any four flowchart symbols?

    Ans: The four flowchart symbols include terminal. input/output, process, and flow line.

    Q. 16. What Is the Importance of flowcharts?

    Ans: The flowchart is an important tool in problem-solving. It can be used to plan the solution in problem-solving. The solution can be understood easily with the help of a flowchart. It also helps the user to verify if the solution is correct or not.

    Q.17. Write any three advantages of the flowchart?

    Ans: The flowchart is easy to draw. It helps to understand the problem solution easily. It clearly shows the flow from one step to another.

    Q. 18. How Is a flowchart constructed?

    Ans: A flowchart is constructed by determining different requirements for the given problem. These requirements include input processing, decision, and output.

    Q.19. How can you show the sequence of the execution of the steps in the flowchart?

    Ans: The sequence of the execution of the steps in the flowchart is shown using the flow lines. The sequence is generally shown from top to bottom.

    Q.20. Which symbol is used to show processing in the flowchart?

    Ans: The rectangle is used to represent a processing or computational operation in the flowchart.

    Q.21. What Is the purpose of parallelogram and rectangle symbols in flowcharts?

    Ans: Parallelogram Is used to represent the input or output step in the flowchart. Rectangle is used to represent a processing or computational operation in the flowchart.

    Q.22. Which symbol is used to start and end the flowchart?

    Ans: The oval symbol is used to start and end the flowchart. It is also called a terminal symbol.

    Q.23. What is the use of a decision symbol?

    Ans: The decision symbol is used to represent the decision in the flowchart. A condition is given in the
    diamond symbol. The flow of control from the diamond symbol may go in two possible directions.
    It goes in one direction if the condition is TRUE and in the second direction if the condition is false.

    Q.24. Define algorithm?

    Ans: An algorithm is a finite number of steps to solve a problem. The steps given in the algorithm
    are in a specific order. The steps may consist of input, process, decision, and output.

    Q.25. Differentiate between flowchart and algorithm?

    Ans: The flowchart uses standard symbols but the algorithm uses simple English. A flowchart is more time-consuming, but the algorithm is less time-consuming. A flowchart is difficult to modify but an algorithm is easier to modify.

    Q.26. What Is the role of algorithm in solving a problem?

    Ans: An algorithm plays an important role in solving a problem. It is the plan for solving the problem. It helps the user to find the solution to the problem. The process of solving a problem becomes simpler and easier with the help of an algorithm.

    Q.27. Is it necessary for an algorithm to solve the problem in a finite number of steps? If yes,
    why?

    Ans: Yes. an algorithm must solve the problem in a finite number of steps. The reason is that the solution to any problem cannot consist of infinite steps. The algorithm has a clear start and end. The solution is found when all steps are performed in a sequence.

    Q.28. What Is the role of input in the efficiency of an algorithm?

    Ans: The role of input is very important in the efficiency of an algorithm. An efficient algorithm must clearly define the required input to solve the problem.

    Q.29. What factors are used to measure the efficiency of an algorithm?

    Ans: The efficiency of an algorithm is measured based on a number of steps in the algorithm and space in computer memory. An algorithm is more efficient if it takes less number of steps to solve a problem. An algorithm Is more efficient if it takes less space in computer memory.

    Q.30. What is test data?

    Ans: The test data is used to check the correctness of an algorithm. It is important to test the output of the algorithm after solving a problem. Different values of test data Are given to the algorithm as input. The output is checked to confirm that the algorithm works correctly.

    Q.31. Why is testing a solution important?

    Ans: Testing is very important to ensure the correctness of the solution. It can be used to find any errors in the solution. It helps the user to modify and improve the solution. “The testing becomes even more critical if the solution is used commercially.

    Q.32. Differentiate between valid and invalid test data?

    Ans: A type of test data that is according to the input requirements of an algorithm is called valid test data. A type of test data that is not according to the input requirements of an algorithm is called invalid test data.

    Q.33. What Is boundary test data?

    Ans: The smallest or the largest data values from the range of valid test data are called boundary
    test data. AA algorithm is tested with the boundary test data to ensure that it handles these
    values correctly.

    Q.34. What do you mean by absent data?

    Ans: The absent data means that the number of values given to a solution is less than expected.

    Q.35. What Is the process of verification?

    Ans: Verification is the process of testing if the solution Is solving the same problem for which it was designed. Suppose an algorithm is prepared to find the percentage of a student and assign the grade. The user can observe if the algorithm inputs marks and displays grades.

    Q.36. What Is the process of validation?

    Ans: Validation is the process of testing If the solution Is correct or not. Suppose an algorithm is prepared to find the percentage of a student and assign the grade. The user can check the output of the algorithm to confirm that the grade Is assigned correctly.

    Q.37. What Is a trace table?

    Ans: A trace table is a technique for testing the algorithm to ensure that it does not have any logical errors. The trace table usually consists of multiple rows and columns. Each column shows the name of the data element. Each row shows the value of the data element in each step

    Download PDF Format

    he class 9 Punjab Textbook of Computer Science is commonly considered the beginning of your technological journey. Besides this book, which is an excellent source for newbies, I would recommend you summarize the others information online. Moreover, This post presents you with the 9th Class Notes for Computer Science. It contains five posts against each chapter. In addition, Chapter posts contain a variety of questions, including Short Questions, Long Questions, and Multiple-Choice Questions.

    Like Our Facebook Page For Educational Updates faizulislam

    These 9th class notes prepared according to the syllabus of all Punjab Boards. Other boards other than Punjab do not follow class 9 computer science notes. These Punjab boards are Gujranwala Board, Lahore Board, Faisalabad Board, Multan Board, Rawalpindi Board, Bahawalpur Board Sargodha Board, DG Khan Board, Sahiwal Board.

  • Class 10th English important questions

    10th class English important questions 2024 Punjab Board

    On this page you will find English estimate paper for class 10 2024 in both English and Urdu. There are two formats to download the best important questions for class 10 English. All the boards in Punjab can use this useful English estimation sheet for class 10. BISE boards in these locations include Faisalabad, Lahore, Gujranwala, Dera Ghazi Khan, Sargodha, Sahiwal, Multan and Jammu Kashmir. Many students practice English Guess Paper 2024 by FAIZ UL ISLAM and get good results in the exam.

    Unit-1

    1. How can people achieve perfection in the moral, spiritual and social areas of life?
    2. What made the non-Muslims bring their suits to the Rasoolﷺ?
    3. Why did non-Muslims trust the Rasoolﷺ?
    4. How did the Rasoolﷺ resolve the issue?
    5. How did the Rasoolﷺ all mankind? set high and noble ideas for all mankind?
    6. How does the Holy Quran describe the personality of the Rasoolﷺ?

    Unit-2

    1. Why does Chinese dinner consist of eight or nine dishes?
    2. What do decorations on doors and windows symbolize?
    3. Why is Chinese New Year never on the same day each year?
    4. What do the little red envelopes filled with money symbolize?
    5. What is the significance of New Year’s Eve dinner?
    6. When does Chinese New Year start?

    Unit-3

    1. What can we learn from failure?
    2. How is failure not a disgrace?
    3. How many times should we try and why?
    4. What should we do if we find our task hard?

    Unit-4

    1. Why is it necessary to keep away soap from the wound?
    2. When do you need to see a doctor?
    3. What should your first-aid kit consist of?
    4. You should not keep checking if the bleeding has stopped. Why?
    5. How is an antibiotic cream or ointment good in healing the wound?

    Unit-5

    1. What will happen after the rain stops?
    2. What do the rich and poor leaves stand for?
    3. What according to the poet is a sweet noise?

    Unit – 6

    1. How is a newspaper more convenient medium of news?
    2. How does television make us lazy?
    3. What is one good thing about newspapers?
    4. Why do some people read more than one newspaper?
    5. How does a viewer get restricted while watching T.V news?
    6. Which medium do you prefer for news? Why?

    Unit-7

    1. What are some distinctions of the writer?
    2. How has the writer spent his summer vacation?
    3. What has he gained from his summer jobs experience?

    Unit-8

    1. What is wind doing to all man’s work?
    2. How does the scene look like when wind is still?

    Unit – 9

    1. What is meant by “right profession”?
    2. How can career counselors help the young people?
    3. What were some famous careers for the young people in the past?
    4. Why is it important to consider the scope of any field?
    5. Which career do you want to opt for? Give reasons?

    Unit-10

    1. How does a book connect the reader and the writer?
    2. Which book has inspired you the most? Why?
    3. In what way books are better than radio, T.V and Internet?
    4. Can modern technology take the place of books?

    Unit-11

    1. What changed Pip’s life?
    2. What kind of boy was Pip?
    3. Who was Joe? How did he treat Pip?
    4. Why did the prisoner support Pip?
    5. Who looked after Pip after the death of his parents?
    6. What happened to the prisoner?

    Unit-12

    1. How are water resources under great stress?
    2. What is the limitation of improved technology?
    3. What is the major cause of food shortage and
    4. malnutrition?
    5. How is fossil energy a finite source?
    6. What is the major cause of food shortage and malnutrition?

    Unit-13

    1. Why did the old man hurl a stone at the camel?
    2. On what condition was the criminal allowed to leave?
    3. Why did the accusers forgive the villager?
    4. What case did the young men bring to Hazrat
    5. Umar Farooq?
    6. Why Were Sahabas worried?

    Download PDF Format

    If you are trying to get 2nd year english guess paper 2024 in pdf then you are at the right place. According to the Punjab Board Syllabus here is Class 12 English Estimate Paper. The role of important questions is very crucial in every student’s life as these papers contain all the important questions that are likely to appear in the final exam. In addition, they provide a detailed description of how the tests will be performed. This happened in the upcoming 12th class annual.

    If you are trying to get 2nd year english assessment paper 2024 pdf then you are at the right place. According to Punjab Board Syllabus here is Class 12 English Review Paper. The role of assessment papers is very important in every student’s life because these papers contain all the important questions that may appear in the final examination. In addition, the assessment papers provide a detailed description of how the exams will be conducted. This is because of the upcoming 12th annual events.

  • Class 10th Physics Important Questions

    10th class Physics Important Question 2024 Punjab Board

    On this page you will find Physics Estimate Paper for class 10 2024 in both English and Urdu. There are two formats to download the most important questions for class 10 physics. All the boards in Punjab can use important physics estimation paper for class 10th. BISE boards in these locations include Faisalabad, Lahore, Gujranwala, Dera Ghazi Khan, Sargodha, Sahiwal, Multan and Jammu Kashmir. Many students practice Physics Estimate Paper 2024 by FAIZ UL ISLAM and get good results in the exam.

    Chapter 10

    Define the wave and wave motion.
    what is S.H.M with mathematical form and features?
    what is spring constant.
    differ b/w restoring and deforming force.
    differ b/w diffraction and refraction of waves.
    Differ b/w crest and trough with sketch.7.what is ripple tank.
    define the wavelength, amplitude and frequency.
    differ b/w oscillations and damped oscillations.
    what is the reflection of waves.
    Differ b/w compression and rarefaction.
    Differentiate b/w mechanical and electromagnetic waves.
    Compare longitudinal waves and transverse waves or types of mechanical waves.
    Who works on a clock and simple pendulum.
    Define the simple pendulam with its mathematical form.
    Define stationary waves. Exercise review questions are: 2,3,4,8,9 conceptual que is 1,4

    Chapter 11

    What are sound waves?
    what is stethoscope and its function.
    what is loudness of sound and its factors.
    define the pitch, quality and intensity of sound.
    give the mathematical form of intensity sound level.
    what is an echo?
    write speed of sound in different mediums.
    differ b/w musical sounds and noise.
    write sources of noise pollution and its effect on human health.
    write importance of acoustics.
    what is reverberation.
    what is audible frequency range.
    what is an ultrasound and write its two uses in daily life.
    what is SONAR.Exercise review que 1,5,8,18 concep 3,7,8,9.

    Chapter 12

    What is the reflection of light and write its types?
    what are laws of reflection.
    what is a spherical mirror and write its types.
    differ b/w concave and convex mirror.
    differ b/w principal axis and principal focus.
    differ b/w radius of curvature and center of curvature.
    define the pole of a mirror.
    differ b/w optical center and focal length.
    what is the refraction of light and write its laws.
    what is refractive index and also write snail,s law.
    what is the total internal reflection and also define the critical angle.
    what are optical fibers.
    what are light pipes.
    define the endoscope within its use.
    define the lense and write its types.
    differ b/w converging and a diverging lens.
    write uses of lenses.
    differ b/w resolving and magnifying power.
    define prism.
    what is telescope and write its types.
    write uses of a compound microscope.
    what is accommodation.
    differ b/w near and far point.
    differ b/w myopia and hypermetropia or defects of vision.
    differ b/w real and virtual focus. Conceptual 4,7,8,10.

    Chapter 13

    write properties of charge.
    define the electrostatic induction.
    what is electroscope.
    differ b/w conductor and insulators.
    define electroscope.
    what is coulombs law.
    differ b/w electric field and electric field intensity.
    what is electrostatic potential.
    differ b/w farad and volt.
    differ b/w capacitor and capacitance.
    write methods to the combination of capacitors.
    compare variable and fixed capacitors.
    write uses of capacitors.
    write applications of electrostatistics.
    write the hazards of static electricity.
    what is electrolytic capacitors.
    what is dielectric. Conceptual 1,3,4.

    Chapter 14

    define the current and ampere.
    what is conventional current.
    differ b/w e.m.f and potential difference.
    what is Ohm’s law.
    write ohmic and nonohmic devices.
    what is resistance and its units. 6.write methods of combination of resistors.
    what is joule law
    differ b/w watt and kilowatt hour.
    what is electric power.
    differ b/w A.C and D.C.
    Define the E,N, and L.
    What is a fuse?
    write safety use of electricity.
    what is galvanometer.
    write sources of e.m.f.
    write uses of the parallel circuit.
    write uses of a fuse.
    what is electric power of washing machine and heater.
    why resistance increased by increasing temperature.
    differ b/w joule and kilo joule.
    how current is measured BY ammeter.Exercise review 2,3,4,6,12. Conceptual 1,2,3,5,7,11

    Chapter 15

    what is the fleming left-hand rule.
    what is a solenoid.
    what is the fleming right-hand rule.
    what is electromagnetic induction.
    write factors affecting the e.m.f.
    what is Lenz’s law.
    differ b/w self and mutual induction.
    define the relay.
    write application of electromagnets.
    differ b/w step-up transformer and step down transformer.
    define electromagnetism.
    compare D.C motor and A.C motor.
    what is A.C generator and its working principle.
    define transformer and how it is work.
    How magnetic force is increased.
    what is Faraday’s law. Review ques 5,6,7,10,11,12, concept 3,6,7.

    Chapter 16

    define electronics.
    define thermionic emission.
    what is C.R.O and its parts.
    what is electron gun.
    what are deflecting plates.
    differ b/w analogue and digital electronics.
    differ b/w ADC and DAC.
    write uses of logic gates.
    compare AND and OR operations.
    compare AND and OR gate.
    how thermonic emnission produced.
    differ b/w digital quantity and digital electronics.
    differ b/w digital and analogue electronics.
    why not gate called invertor.
    what are BITS or digitalization.
    what are house safety alarms.
    what is bolean variable.
    how many basic operations of digital electronics.
    write universal logic gates.
    write factors of thermonic emission and how is produced.
    what are truth tables. Rview 3,5,9,10 conceptual 1,6

    Chapter 17

    what is I.C.T.
    differ b/w hardware and software.
    what is data.
    differ b/w cell phone and photophones.
    what is computer and write its parts.
    differ b/w primary and secondary storage devices.
    define the hard disc,compact disc and magnetic disc.
    what are applications of computer.
    what is the internet.
    what is electronic mail and its use.
    write components of CBIS.
    write input and output devices.
    write uses of the internet.
    what is floppy disc.
    what is internet service.
    what is a global web.
    differ b/w RAM and ROM.
    What are the language of a computer?
    what is information.Review que 5,7,12 concept 1,2

    Chapter 18

    what are isotopes and write hydrogen isotopes.
    differ b/w natural radioactivity and radioactive elements.
    what are background information.
    what is nuclear transmutation.
    write two properties of alpha, beta, and gamma.
    differ b/w ionizing effect and penetrating ability.
    define half life
    what are radioisotopes and also define artificial radioisotopes.
    differ b/w fission and fusion reaction.
    what are a chain reaction and how it is controlled.
    differ b/w parent and daughter nuclei.
    what is carbon dating.what is the use of radioisotopes in medical FIELD.
    What are the hazards of radiations and its preventive measures?
    differ b/w stable and unstable nuclei.
    differ b/w mass number and atomic number.
    what is ATM and write its fundamental particles.Review que 3,4,10 concept 1,3.

    Download PDF Format

    When preparing for their final exam, students can use the 9th grade physics assessment paper. Every chapter in the textbook is covered along with questions to be asked in the exam. These essential questions can be used as study aids after students have completed the entire book. By doing this, students can identify key concepts to focus on and gauge their understanding. As a result, important questions can boost students’ confidence and help them perform well in exams.

    class 10 Physics Estimate Paper 2024 for Punjab Board Students

    In fact, physics is considered to be a very difficult subject. class 10 exam date paper has been released as per all school board. All Punjab Boards will conduct Physics Papers on Friday. Therefore, there is little time for exam preparation. You can use these important questions to prepare for the board exam by covering all the important questions.

    In addition, you will improve your knowledge and prepare for the important questions that will come in these exams. One of the main features of our useful requests is that they can be downloaded for free. This means you can download and even print these important questions for free. However, on these exam days you can get and use these important questions for free even though these important questions are more expensive.