GROUP II PAPER I Chemistry 1. One example of a chemical used in toothpaste is (a) chlorine(b) sulphur (c) carbon dioxide(d) calcium carbonate

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1 GROUP II PAPER I Chemistry 1. One example of a chemical used in toothpaste is (a) chlorine(b) sulphur (c) carbon dioxide(d) calcium carbonate 2. When a part of the body is injured, substances called are released. (a) aspirins (b) pain relievers (c) nitrogen oxides (d) chiorofluorocarbons 3. Which of the following is acompound? (a) mercury (Hg) in a gauge (b) salt (NaCI) in a shaker (C) aluminium (Al) in a can (d) gold (Au) in a ring 4. Refrigerating perishable foods affects biochemical reactions by (a) increasing concentrations of antioxidants. (b) removing bacteria. (C) decreasing the rate of reactions affecting spoilage. (d) catalyzing the removal of harmful chemicals from the foods. 5. When gold is melted and formed in a mold to make a piece of jewellery what type of change is taking place? (a) a chemical change(b) a change of size (C) evaporation(d) a physical change 6. Which one of the following properties describes a liquid? (a) It has its own shape. (b) 115 particles are close together and move randomly. (C) Its particles move very rapidly. (d) It fills the entire volume of the container. 7. In any chemical reaction, the rateof the reaction can be increased by (a) decreasing the temperature. (b) changing the size of the container. (C) adding water to the reaction. (d) increasing the concentrations of the reactants. 8.Vinegar is a solution of acetic acid(melting point 5 C) in water. At room temperature (25 C), vinegar is an example of a solution. (a) liquid liquid(b) gas liquid (c) solid liquid(d) Solid solid 9. The green colour of copper exposedto air is due to of the surface of the copper. (a) oxidation (b) reduction (c) galvanization (d) decomposition 10. Ethanol is (a) organic. (C) a nutrient. (b) essential. (d) inorganic. 11.Conversion of a substance directly from solid to vapour State is known as (a) Vaporization (b) Sublimation (C) Decomposition (d) Ionization 12. The chemical name of bauxite is (a) aluminium oxide (b) aluminium chloride (c) aluminiumsulphite (d) anhydratedaluminium oxide 13. Properties of element aredetermined by (a) Atomic number (b) Atomic weight (C) Neutrons (d) Protons 14. Milk is pasteurized in order to (a) destroy microorganisms (b) enhance taste and flavour (C) increase its food value (d) detect adulteration 15. The chemical composition of four well known items which are used in large

2 quantities are given below. Which one is incorrect? (a) Washing soda: sodium,hydrogen and aluminium (b) Caustic soda: sodium, hydrogen and oxygen (c) Baking soda: sodium,hydrogen, oxygen and carbon (d) Common salt: sodium and chlorine 16. Match the following: (A) Carbon dioxide (B) Chlorine (C) Hydrogen (d) Nitrous oxide 1. Reducing agent 2. Anaesthetic in dentistry 3. Bleaching powder 4. Refrigerant (a) (b) 4 3 2

3 (C) haematite (d) monazite 31. Which of the following is alwaysfound in a free state in nature? (a) Gold (b) Silver (C) Sodium (d) Copper 32. When zinc reacts with hydrochloric acid. the gas evolved Is (a) oxygen (b) hydrogen (C) chlorine (d) none of these 33. Molish s test is used to (a) measure acidity of a solution (b) detect carbohydrates in a solution (C) check traces of alkali in asolution (d)identify certain elements in a solution 34. Faraday s law is associated with (a) electrolysis (b) reaction of gases (c) pressure of gases (d) temperature and pressure 35. Which of the following laws does not relate to gases? (a) Boyle s law (b) Charles s law (c) Gay-Lussac s law (d) Faraday s law 36. Which of the following is a physical change? (a) Souring of milk (b) Magnetizing of an iron rod (C) Corrosion of metal (d) Explosion 37. Which of the following is a basic oxide? (a) N2O5 (b) Na2O(c) CO2 (d) SO3 38. Match the following (A) Barium 1. B (B) Boron 2. Hg (C)Mercury 3. Ba (D)Lead 4.Pb (a) (b) (c) (d) Match the following: Acids (A) Lactic acid (B) Acetic acid (C) Citric acid (D) Butyric acid Present in 1. lemon 2. rancid butter 3. milk 4. vinegar (a) (b) (c) (d) Which of the following is a normetallic mineral? (a) Bauxite (b) Gypsum (C) Magnesium (d) Manganese 41. Material used for bleaching pulp is (a) lime (b) alum (c) sodiumhypochioride(d) caustic soda 42. Which metal forms an amalgam with other metals? (a) Tin (b) Zinc(C) Mercury (d) Lead 43. What is dry ice? (a) Calcium hydroxide (b) Solid carbon dioxide (c) Sodium hydroxide (d) None of these 44. Chemical change does not take place in (a) souring of milk into curd (b) rusting of iron in atmosphere (c) burning of magnesium ribbon in air

4 (d) emitting of light by a red hotplatinum wire 45.An example of an element is (a) water (b) sulphuric acid (c) chlorine (d) sulphur dioxide 46. The allotropic form of phosphorus used in match industry is (a) alpha black phosphorus (b) white phosphorus (c) red phosphorous (d) beta black phosphorus 47. Most commonly used bleaching agent is (a) carbon dioxide (b) alcohol (C) chlorine (d) sodium carbonate 48. Petroleum consists of a complex mixture of (a) carbonates (b) carbohydrates (c) hydrocarbons (d) none of these 49. Lime is sometimes applied to soil inorder to (a) increase the acidity of the soil (b)increase the alkalinity of the soil (C) decrease the alkalinity of thesoil (d) restore the nitrates to the soil 50. Sea water is saltier than rain water because (a) the air around sea is salty (b) sea beds have salt deposits (c) rivers wash away salts from the Earth s crust and pour theseinto sea (d) sea animals are salt producing

5 Chemistry key 1.d 2.c 3.b 4.c 5.d 6.b 7.d 8.a 9.a 10.a 11.b 12.d 13.a 14.a 15.a 16.c 17.b 18.b 19.a 20.d 21.b 22.a 23.c 24.d 25.a 26.d 27.c 28.b 29.b 30.a 31.a 32.b 33.b 34.a 35.d 36.b 37.b 38.d 39.c 40.b 41.c 42.c 43.b 44.d 45.c 46.c 47.c 48.c 49.b 50.c