1. Which noble gas is used in cancer treatment?
a) Helium
b) Argon
c) Krypton
d) Radon
Answer: d
2. Which of the following metals has the lowest density?
a) Lithium
b) Iron
c) Gold
d) Vanadium
Answer: a
3. What is a key component in a dry powder fire extinguisher?
a) Sand
b) Sand + Sodium carbonate
c) Sand + Potassium carbonate
d) Sand + Sodium bicarbonate
Answer: d
4. Which is the most reactive element among the following?
a) Potassium
b) Calcium
c) Lead
d) Copper
Answer: a
5. Sodium is generally stored under:
a) Alcohol
b) Water
c) Ammonia
d) Kerosene
Answer: d
6. Which of the following cannot be beaten into sheets?
a) Gold
b) Silver
c) Argon
d) Aluminium
Answer: c
7. Water has maximum density at:
a) 0°C
b) 4°C
c) 100°C
d) 273°C
Answer: b
8. Metals react with sodium hydroxide to release:
a) Oxygen
b) Sodium
c) Water
d) Hydrogen gas
Answer: d
9. Which gas is commonly used to fill balloons?
a) Hydrogen
b) Helium
c) Carbon dioxide
d) Oxygen
Answer: b
10. What is formed when magnesium is burned?
a) Baking soda
b) Calcium carbonate
c) Ash
d) Vinegar
Answer: c
11. What is the chemical name of common salt?
a) Calcium carbonate
b) Sodium carbonate
c) Sodium chloride
d) None of these
Answer: c
12. Why is helium used in balloons?
a) Its atomic number is 2
b) It is lighter than air
c) It’s part of water molecules
d) It’s a noble gas
Answer: b
13. Plaster of Paris is made from:
a) Marble
b) Bauxite
c) Limestone
d) Gypsum
Answer: d
14. The most common bleaching agent is:
a) Carbon dioxide
b) Alcohol
c) Chlorine
d) Sodium chloride
Answer: c
15. Match the following:
A. Blue vitriol – 4. Copper sulphate
B. Epsom salt – 3. Magnesium sulphate
C. Baking soda – 1. Sodium bicarbonate
D. Caustic soda – 2. Sodium hydroxide
Correct code: A–4, B–3, C–1, D–2
Answer: d
16. Baking soda is:
a) Aluminium bicarbonate
b) Sodium isolate
c) Sodium bicarbonate
d) Aluminium sulphate
Answer: c
17. Most mine explosions are caused by a mix of:
a) Hydrogen and oxygen
b) Oxygen and acetylene
c) Methane and air
d) Carbon dioxide and ethane
Answer: b
18. The chemical name of baking soda is:
a) Sodium carbonate
b) Sodium bicarbonate
c) Sodium chloride
d) Sodium nitrate
Answer: b
19. Which of the following is both hard and highly ductile?
a) Carborundum
b) Tungsten
c) Cast iron
d) Nichrome
Answer: d
20. Which of these statements is/are correct?
- Baking soda is used in fire extinguishers
- Quicklime is used in glass production
- Gypsum is used to make plaster of Paris
Answer: d) 1, 2 and 3
21. Who discovered nitrogen?
a) Faraday
b) Heisenberg
c) Hooke
d) Rutherford
Answer: d
22. Sodium tetraborate decahydrate is commonly known as:
a) Epsom salt
b) Gypsum
c) Borax
d) Galena
Answer: c
23. In blast furnaces, coke acts as:
a) A reducing agent and heat source
b) Silica remover
c) Oxidizing agent
d) None of the above
Answer: c) 1 and 3 are correct
24. Match the following:
A. Potassium bromide – 2. Photography
B. Potassium nitrate – 4. Gunpowder
C. Potassium sulphate – 1. Fertilizer
D. Monopotassium tartrate – 3. Bakery
Correct code: A–2, B–4, C–1, D–3
Answer: a
25. Anodized aluminium means it has a coating of:
a) Chromium oxide
b) Aluminium oxide
c) Nickel oxide
d) Zinc oxide
Answer: b
26. Which metal salts give color to fireworks?
a) Zinc and sulfur
b) Potassium and mercury
c) Strontium and barium
d) Chromium and nickel
Answer: c
27. Chemical formula of washing soda is:
a) Na₂SO₄·10H₂O
b) Na₂CO₃·10H₂O
c) NaHCO₃
d) Ca(OH)₂
Answer: b
28. Which mineral does not contain oxygen?
a) Haematite
b) Bauxite
c) Cryolite
d) Calcite
Answer: c
29. Gypsum is used to improve:
a) Podsols
b) Acidic soils
c) Alkaline soils
d) Saline soils
Answer: d
30. Which statement is incorrect about carbon compounds?
a) They have low melting and boiling points
b) Insoluble in water
c) Not easily combustible
d) Mainly contain carbon and hydrogen
Answer: a
31. Potassium nitrate is primarily used in:
a) Health drinks
b) Fertilizers
c) Textiles
d) None of these
Answer: b
32. Which metal is used in thermometers?
a) Zinc
b) Lead
c) Mercury
d) Tin
Answer: c
33. The silver salt used in photography is:
a) Silver bromide
b) Silver chloride
c) Silver sulphate
d) Silver nitrate
Answer: a
34. Misch metal is widely used in manufacturing:
a) Car brakes
b) Smoke detectors
c) Cigarette lighters
d) Emergency lights
Answer: c