1. Elements, Metals & Non-Metals
1. Which of the following is the lightest metal?
(A) Mercury
(B) Lithium
(C) Lead
(D) Silver
Answer: (B) Lithium
2. Which metal is liquid or melts near room temperature, apart from mercury?
(A) Cesium
(B) Gallium
(C) Bromine
(D) Sodium
Answer: (B) Gallium
3. Which is the heaviest naturally occurring element on Earth?
(A) Lead
(B) Thorium
(C) Plutonium
(D) Uranium
Answer: (D) Uranium
4. An element that does not occur naturally but can be produced artificially is:
(A) Thorium
(B) Radium
(C) Plutonium
(D) Uranium
Answer: (C) Plutonium
5. Which of the following is a halogen?
(A) Sodium
(B) Fluorine
(C) Calcium
(D) Iron
Answer: (B) Fluorine
6. Select the non-metal with a shiny appearance.
(A) Gold
(B) Silver
(C) Iodine
(D) Sodium
Answer: (C) Iodine
7. Which element is present in chlorophyll?
(A) Magnesium
(B) Calcium
(C) Iron
(D) Manganese
Answer: (A) Magnesium
8. When most metals react with dilute acids, the gas generally evolved is:
(A) Oxygen
(B) Hydrogen
(C) Nitrogen
(D) Carbon dioxide
Answer: (B) Hydrogen
9. The word “atom” comes from a Greek word meaning:
(A) Small
(B) Indivisible
(C) Unseen
(D) Visible
Answer: (B) Indivisible
10. What type of bond involves the sharing of electron pairs between atoms?
(A) Ionic bond
(B) Hydrogen bond
(C) Metallic bond
(D) Covalent bond
Answer: (D) Covalent bond
2. Carbon, Hydrocarbons & Fuels
11. Diamond is an allotrope of:
(A) Carbon
(B) Silicon
(C) Sulphur
(D) Germanium
Answer: (A) Carbon
12. Which of the following materials has the highest density and hardness?
(A) Graphite
(B) Charcoal
(C) Coke
(D) Diamond
Answer: (D) Diamond
13. Which of the following is used in pencils?
(A) Graphite
(B) Silicon
(C) Charcoal
(D) Phosphorus
Answer: (A) Graphite
14. Liquid hydrocarbons are converted to low-molecular-weight gaseous hydrocarbons by a process known as:
(A) Hydrogenation
(B) Cracking
(C) Oxidation
(D) Reduction
Answer: (B) Cracking
15. Which substance is the primary component of natural gas?
(A) Helium
(B) Methane
(C) Oxygen
(D) Nitrogen
Answer: (B) Methane
16. Biogas / Gobar gas comprises mostly of:
(A) Methane and carbon dioxide (Methane is the chief combustible component)
(B) Sulphur dioxide
(C) Nitrogen and ammonia
(D) Carbon monoxide
Answer: (A) Methane and carbon dioxide
17. Cooking gas is a mixture of:
(A) Oxygen and carbon dioxide
(B) Oxygen and carbon monoxide
(C) Propane and butane
(D) Hexane and methane
Answer: (C) Propane and butane
18. Tetraethyl lead was historically used as:
(A) A painkiller
(B) A fire extinguisher
(C) A mosquito repellent
(D) A petrol additive
Answer: (D) A petrol additive
3. Common Chemicals, Compounds & Mixtures
19. Which one of the following is called “dry ice”?
(A) Liquid carbon dioxide
(B) Solid carbon dioxide
(C) Liquid nitrogen
(D) Solid nitrogen
Answer: (B) Solid carbon dioxide (CO₂)
20. Which of the following is also known as laughing gas?
(A) Nitrogen dioxide
(B) Nitrogen tetroxide
(C) Nitrogen trioxide
(D) Nitrous oxide
Answer: (D) Nitrous oxide
21. Quicklime is chemically:
(A) CaCO₃
(B) CaO
(C) Ca(OH)₂
(D) NaOH
Answer: (B) CaO
22. Which substance produces a hissing sound when dissolved in water?
(A) Limestone
(B) Slaked lime
(C) Soda lime
(D) Quicklime
Answer: (D) Quicklime
23. The chemical name of limestone is:
(A) Calcium chloride
(B) Calcium oxide
(C) Calcium carbonate
(D) Calcium
Answer: (C) Calcium carbonate
24. The principal raw material used in cement manufacture is:
(A) Gypsum
(B) Limestone
(C) Ash
(D) Sodium chloride
Answer: (B) Limestone
25. The principal chemical component of baking powder / the chemical formula of baking soda is:
(A) NaCl
(B) CaCO₃
(C) NaHCO₃ (Sodium hydrogen carbonate)
(D) Ca(OCl)₂
Answer: (C) NaHCO₃ (Sodium hydrogen carbonate)
Note: Strictly speaking, sodium hydrogen carbonate (baking soda) is a component of baking powder; baking powder itself is a mixture.
26. Which of the following is commonly described as a supercooled liquid?
(A) Mercury
(B) Bromine
(C) Glass
(D) Ice cream
Answer: (C) Glass
27. Quartz is chemically:
(A) Silicon dioxide
(B) Germanium oxide
(C) Sodium silicate
(D) Calcium silicate
Answer: (A) Silicon dioxide
28. Which of the following is a nitrogenous fertilizer?
(A) Ammonium sulphate
(B) Potassium chloride / Sulphur phosphate
(C) Calcium carbonate / Potassium nitrate
(D) Sodium chloride
Answer: (A) Ammonium sulphate
29. Potassium permanganate purifies water mainly because it acts as:
(A) A reducing agent
(B) An oxidizing agent
(C) A solvent
(D) A catalyst
Answer: (B) An oxidizing agent
30. Which of the following gases is commonly filled in food packages?
(A) Argon
(B) Nitrogen
(C) Oxygen
(D) Hydrogen
Answer: (B) Nitrogen
31. Tear gas used by the police to disperse mobs commonly contains:
(A) Carbon dioxide
(B) Chlorine
(C) Ammonia
(D) Hydrogen sulphide
Answer: (B) Chlorine
4. Alloys & Materials Science
32. Brass is an alloy of:
(A) Zinc and iron
(B) Copper and zinc
(C) Copper and tin
(D) Iron and mercury
Answer: (B) Copper and zinc
33. Brass gets discoloured in air mainly because of the presence of:
(A) Oxygen
(B) Hydrogen sulphide
(C) Carbon dioxide
(D) Nitrogen
Answer: (B) Hydrogen sulphide
34. Bronze is an alloy of:
(A) Zinc and iron
(B) Copper and tin
(C) Tin and zinc
(D) Iron and mercury
Answer: (B) Copper and tin
35. Galvanized iron sheets have a coating of:
(A) Lead
(B) Chromium
(C) Zinc
(D) Tin
Answer: (C) Zinc
36. The most important ore of aluminium is:
(A) Bauxite
(B) Magnetite
(C) Haematite
(D) Monazite
Answer: (A) Bauxite
37. The heating coil of an electric heater is made of:
(A) Platinum
(B) Tungsten
(C) Nichrome
(D) Brass
Answer: (C) Nichrome
38. The substance added to make natural rubber stronger and more elastic is:
(A) Polythene
(B) Phosphorus
(C) Sulphur
(D) Iodine
Answer: (C) Sulphur
39. Bakelite is:
(A) A natural rubber
(B) A synthetic plastic
(C) A metal alloy
(D) A ceramic
Answer: (B) A synthetic plastic
40. In which of the following activities is silicon carbide used?
(A) Making cement and glass
(B) Disinfecting water of ponds
(C) Cutting or grinding very hard substances
(D) Making casts for statues
Answer: (C) Cutting or grinding very hard substances
41. Which of the following compounds has been used in fireproofing materials?
(A) Aluminium chloride
(B) Aluminium sulphate
(C) Magnesium chloride
(D) Magnesium sulphate
Answer: (C) Magnesium chloride
42. Mordants are substances that:
(A) Fix colours on fabrics
(B) Have a bleaching action
(C) Have the capacity to increase the intensity of colour
(D) Are edible salts
Answer: (A) Fix colours on fabrics
43. What does the airbag used for the safety of a car driver contain (to generate nitrogen gas)?
(A) Sodium bicarbonate
(B) Sodium azide
(C) Sodium nitrite
(D) Sodium peroxide
Answer: (B) Sodium azide
5. Organic Chemistry, Biochemistry & Physical Properties
44. What type of reaction is saponification?
(A) Hydrolysis reaction
(B) Substitution reaction
(C) Addition reaction
(D) Combustion reaction
Answer: (A) Hydrolysis reaction
45. Which acid is present in an ant sting?
(A) Acetic acid
(B) Formic acid
(C) Hydrochloric acid
(D) Butyric acid
Answer: (B) Formic acid
46. The chemical name of Vitamin C is:
(A) Citric acid
(B) Ascorbic acid
(C) Oxalic acid
(D) Nitric acid
Answer: (B) Ascorbic acid
47. Which natural sugar is found in milk?
(A) Lactose
(B) Maltose
(C) Fructose
(D) Sucrose
Answer: (A) Lactose
48. The chemical formula of lactose is:
(A) C₁₂H₆O₁₂
(B) C₁₂H₂₂O₁₁
(C) C₁₂H₂₃O₃₄
(D) C₁₂H₁₃O₁₄
Answer: (B) C₁₂H₂₂O₁₁
49. Sucrose is a:
(A) Monosaccharide
(B) Disaccharide
(C) Polysaccharide
(D) Protein
Answer: (B) Disaccharide
50. How many different types of elements are present in glucose (C₆H₁₂O₆)?
(A) 2
(B) 3 (Carbon, Hydrogen, Oxygen)
(C) 6
(D) 12
Answer: (B) 3
51. When water freezes, its density:
(A) Increases
(B) Decreases
(C) Becomes zero
(D) Remains constant
Answer: (B) Decreases
52. The density of water is maximum at:
(A) 0°C
(B) 4°C
(C) 100°C
(D) 273°C
Answer: (B) 4°C
53. A common fluorescent tube contains:
(A) Sodium vapour
(B) Argon at low pressure
(C) Mercury vapour at low pressure
(D) Neon at low pressure
Answer: (C) Mercury vapour at low pressure