9th Class Chemistry First half Book Paper

Q1. Multiple choice questions (Attempt all · 60 × 0.5 = 30)

1. Oxidation involves:
   1. loss of electrons
   2. gain of electron
   3. gain of hydrogen
   4. none of these
2. What is the mass of carbon present in 44 g of carbon dioxide?
   1. 12 g
   2. 6 g
   3. 24 g
   4. 44 g
3. Differentiate between accuracy and precision.
4. Pure Form of matter having particular characteristics is called:
   1. Mixture
   2. Substance
   3. Both a & b
   4. None of these
5. Who discovered atomic number?
   1. Moseley
   2. Bohr
   3. Rutherford
   4. Cannizaro
6. Benzene is:
   1. Polar compound
   2. Non-polar compound
   3. Homoatomic compound
   4. Monoatomic compound
7. Which is not released in an aerobic respiration?
   1. Carbon dioxide
   2. Water
   3. Energy
   4. Lactic acid
8. Concentration of reactants and products at equilibrium remains unchanged if:
   1. concentration of any reactant or product is not changed
   2. temperature of the reaction is not changed.
   3. pressure or volume of the system is not changed.
   4. all of the above are observed.
9. Which isotope is commonly used to irradiate cancer cells?
   1. Iodine-123
   2. Carbon-14
   3. Cobalt-60
   4. Iodine-131
10. Consider the reaction: H₂O + HCl ⇌ H₃O⁺ + Cl⁻. Which species is a proton acceptor in this reaction?
    1. H₂O
    2. HCl
    3. H₃O⁺
    4. none
11. Oxidation is shown by:
    1. metals
    2. non-metals
    3. both a and b
    4. none of these
12. Number of particles in one mole of a substance is called:
    1. Atomic number
    2. Particle number
    3. Avogadro’s number
    4. Mass number
13. List some properties of water?
14. Anything that has mass and occupies space is called.
    1. liquid
    2. gas
    3. solid
    4. matter
15. Which of the following elements belongs to VIII A?
    1. Na
    2. Mg
    3. Br
    4. Xe
16. The atoms having less than 2 or 8 electrons in their valence shell are:
    1. Stable
    2. Inreactive
    3. Unstable
    4. Noble gases
17. If the value is negative then reaction will be:
    1. Exothermic
    2. Endothermic
    3. May or may not be Exothermic or Endothermic
    4. None of these
18. Which is true about the equilibrium state?
    1. The forward reaction stops.
    2. The reverse reaction stops.
    3. Both forward and reverse reaction stop.
    4. Both forward and reverse reaction continue at the same rate.
19. The force present between nucleus and electron is electrostatic force of :
    1. Attraction
    2. Repulsion
    3. Both a, b
    4. None of these
20. Milk of magnesia contains Mg(OH)₂. It is used as antacid. It neutralizes excess stomach acid. Which salt is formed in this reaction?
    1. MgSO₄
    2. MgCO₃
    3. MgCl₂
    4. MgO
21. Silver tarnish in the presence of:
    1. SO₂
    2. H₂S
    3. Both a and b
    4. None of these
22. What is the molar mass of H₃PO₄?
    1. 58.5
    2. 98
    3. 40
    4. 48
23. Fatima has fond of junk food like French fries, burgers, and pizza. What will happen if Fatima only eats junk food? What should she add to her routine food?
24. Macroscopic properties are properties that can be visualized by:
    1. the naked eye
    2. microscope
    3. electron microscope
    4. telescope
25. What is the sheilding effect?
    1. increase in nuclear charge
    2. decrease in atomic size
    3. reduction in force
    4. increase in ionization energy
26. Which of the following is not true about the formation of Na₂S:
    1. Each sodium atom loses one electron
    2. Sodium forms cation
    3. Sulphur forms anion
    4. Each sulphur atom gains one electron
27. Activation energy of a chemical reaction must be ________ the average kinetic energy of reacting molecules.
    1. Lower than
    2. greater than
    3. equal to
    4. None of these
28. Which of the following does not happen, when a system is at equilibrium state?
    1. forward and reverse reactions stop.
    2. forward and reverse rates become equal.
    3. concentration of reactants and products stop changing
    4. reaction continues to occur in both the directions.
29. Which isotopes is commonly used to irradiate cancer cell.
    1. Iodine -123
    2. Carbon -14
    3. Cobalt-60
    4. Iodine-131
30. Which of the following cannot be classified as Arrhenius acid?
    1. HNO₃
    2. H₂CO₃
    3. CO₂
    4. H₂SO₄
31. Stainless steel is an alloy of :
    1. Iron
    2. Chromium
    3. Nickel
    4. All of these
32. What is the formula mass of CuSO₄·5H₂O?
    1. 159.5
    2. 185.5
    3. 249.5
    4. 149.5
33. What do you mean by paper chromatogram?
34. Impure matter is also known as:
    1. Atom
    2. Substance
    3. Mixture
    4. Compound
35. How does electron affinity change as you move down a group?
    1. increase
    2. decreases
    3. remains constant
    4. fluctuates
36. Which of the following atoms obey duplet rule?
    1. O₂
    2. F₂
    3. H₂
    4. N₂
37. A catalyst increases the rate of a chemical reaction by:
    1. increasing activation energy
    2. increasing the enthalpy of reaction
    3. Decreasing the enthalpy of reaction
    4. None of these
38. In an irreversible reaction equilibrium is:
    1. established quickly
    2. established slowly
    3. never established
    4. established when reaction stops.
39. When Rutherford was awarded noble prices?
    1. 1909
    2. 1960
    3. 1908
    4. 1925
40. Which of the following is a Bronsted base?
    1. NH₃
    2. HCl
    3. CH₃COOH
    4. H₃O⁺
41. Reduction involves:
    1. loss electrons
    2. gain electrons
    3. loss of hydrogen
    4. none of these
42. Which term is same for one mole of oxygen and one mole of water?
    1. volume
    2. mass
    3. atoms
    4. molecules
43. The branch of chemistry that focuses on the study of polymers, their types, properties, uses is called:
    1. Industrial Chemistry
    2. Polymer chemistry
    3. Organic Chemistry
    4. Astrochemistry
44. Oxygen has two allotropic forms:
    1. O2, O4
    2. O2, O3
    3. O, O
    4. O2, O
45. As you move from right to left across a period, which of the following does not increase:
    1. electron affinity
    2. ionization energy
    3. nuclear charge
    4. shielding effect
46. Atoms achieve stability by attaining electronic configuration of:
    1. Halogens
    2. Transition metals
    3. Noble gases
    4. Non-metals
47. All chemical reactions involve:
    1. Catalysts
    2. Enzymes
    3. Energy changes
    4. All of these
48. When a mixture of H₂(g) and I₂(g) is sealed in a flask and temperature is kept at 25°C, equilibrium is established: H₂(g) + I₂(g) ⇌ 2HI(g). Which substance(s) will be present in the equilibrium mixture?
    1. H₂ and I₂
    2. HI only
    3. H₂ only
    4. H₂, I₂ and HI
49. What is the percentage abundance of deuterium?
    1. 0.9999
    2. 0.000015
    3. 0.988
    4. 0.011
50. Ammonia is a base, because it:
    1. ionizes in water to give OH⁻ ions
    2. Contains OH group
    3. Can accept an election pair
    4. Can accept proton
51. In which of the following changes, the nitrogen atom is reduced.
    1. N₂ to NO
    2. N₂ to NO₂
    3. N₂ to NH₃
    4. N₂ to HNO₃
52. A compound Na₂CX₃ has formula mass 106 amu. Atomic mass of X is:
    1. 106
    2. 23
    3. 12
    4. 16
53. The study of the interaction between drugs and biological targets, as well as the development of new medicinal agents.
    1. Organic chemistry
    2. Medicinal chemistry
    3. Inorganic chemistry
    4. Environmental chemistry
54. Anything that has mass and occupies space is called:
    1. Matter
    2. Substance
    3. Element
    4. Compound
55. Which of the following groups contain alkaline earth metals?
    1. I A
    2. II A
    3. VII A
    4. VIII A
56. Why do atom react?
57. What is visualized by using scanning tunneling microscope?
    1. Siz e of atom
    2. Protons
    3. Electrons
    4. Neutrons
58. Which act as anode in cathodic protection method?
    1. Mg
    2. Al
    3. Both a and b
    4. None of these
59. Gram atom of Na is equal to:
    1. 23 amu
    2. 23 g
    3. 24 amu
    4. None
60. What are the advatanges of using scientific tools like measuring cylinders, stopwatch and thermometers in measurements?