Which element has the lowest melting point?
a) Iron
b) Nitrogen
c) Iodine
d) Lead
Answer: b
2. The filament of an electric bulb is made of:
a) Magnesium
b) Lead
c) Tin
d) Tungsten
Answer: d
3. Among the following, which element has the lowest melting point?
a) Oxygen
b) Platinum
c) Sodium
d) Tin
Answer: a
4. Which of the following elements has the lowest melting point?
a) Chromium
b) Hydrogen
c) Zinc
d) Silver
Answer: b
5. Fullerene, a newly discovered crystalline allotrope of carbon, contains:
a) 100 carbon atoms
b) 80 carbon atoms
c) 60 carbon atoms
d) 40 carbon atoms
Answer: c
6. The chemical formula of ammonium nitrate is:
a) (NH₃)₂NO₃
b) NH₄NO₃
c) NH₄(NOC)
d) NH₂NO₃
Answer: b
7. Which property is generally exhibited by non-metals?
a) Brittleness
b) Conductivity
c) Ductility
d) Malleability
Answer: a
8. Which element has the lowest melting point?
a) Titanium
b) Sulphur
c) Argon
d) Zinc
Answer: c
9. One carat of diamond equals:
a) 100 mg
b) 150 mg
c) 200 mg
d) 250 mg
Answer: c
10. Chemically, washing soda is:
a) Aluminium bicarbonate
b) Sodium bicarbonate
c) Aluminium sulphate
d) Sodium carbonate
Answer: d
11. Which of the following is used as a lubricant?
a) Germanium
b) Sulphur
c) Graphite
d) Indium
Answer: c
12. Which of the following statements is incorrect?
a) Hydrogen atom is roughly one-third the mass of tritium
b) Deuterium is also called heavy hydrogen
c) Deuterium has one neutron
d) Protium is the rarest isotope of hydrogen
Answer: d
13. What material is used in pencils?
a) Charcoal
b) Graphite
c) Sulphur
d) Phosphorus
Answer: b
14. Zeolite is chemically:
a) Hydrated ferric oxide
b) Hydrated sodium aluminium silicate
c) Sodium hexametaphosphate
d) Sodium tetraborate
Answer: b
15. The essential metal in chlorophyll is:
a) Sodium
b) Potassium
c) Manganese
d) Magnesium
Answer: d
16. Which metal is commonly used as an electromagnet?
a) Iron
b) Copper
c) Nickel
d) Cobalt
Answer: a
17. The purest form of carbon is:
a) Anthracite
b) Lampblack
c) Graphite
d) Wood charcoal
Answer: a
18. Which two metals have natural colors other than silver?
a) Nickel and Zinc
b) Copper and Gold
c) Palladium and Platinum
d) Sodium and Magnesium
Answer: b
19. Silica gel is used as a:
a) Moisturizer
b) Flavouring agent
c) Drying agent
d) Preservative
Answer: c
20. Barium must lose how many electrons to attain a noble gas configuration?
a) 1
b) 2
c) 3
d) 4
Answer: b
21. Which gas is commonly used as an anaesthetic?
a) Methane
b) Carbon dioxide
c) Nitrous oxide
d) Nitrogen
Answer: c
22. Which of the following is the poorest conductor of electricity?
a) Iron
b) Lead
c) Silver
d) Gold
Answer: b
23. Which form of phosphorus is most reactive?
a) Black phosphorus
b) White phosphorus
c) Violet phosphorus
d) Red phosphorus
Answer: b
24. Metallic lustre is primarily due to:
a) Dense atomic packing
b) Polished surfaces
c) Reflection of light by free electrons
d) Absorption of light by atoms
Answer: c
25. Which gas is used in the manufacture of bleaching powder?
a) Oxygen
b) Hydrogen
c) Nitrogen
d) Chlorine
Answer: d
26. Which element acts both as a metal and a non-metal (metalloid)?
a) Argon
b) Carbon
c) Xenon
d) Boron
Answer: d
27. Argon is used in arc welding because of its:
a) Inertness and low reactivity with metal
b) Ability to lower melting point
c) High flammability
d) High calorific value
Answer: a
28. Which of the following is known as “brown coal”?
a) Anthracite
b) Bituminous
c) Coke
d) Lignite
Answer: d
29. Which fuel causes the least environmental pollution?
a) Diesel
b) Kerosene
c) Hydrogen
d) Coal
Answer: c
30. Which metal is known as the “king of metals”?
a) Gold
b) Silver
c) Iron
d) Aluminium
Answer: a
31. The purest natural form of water is:
a) Rainwater
b) Lake water
c) River water
d) Sea water
Answer: a
32. What is the gold content in 18-carat gold?
a) 100%
b) 80%
c) 75%
d) 60%
Answer: c
33. Which of the following is a good electrical conductor?
a) Graphite
b) Diamond
c) Peat
d) Charcoal
Answer: a
34. Which metal remains liquid at room temperature?
a) Mercury
b) Platinum
c) Lead
d) Zinc
Answer: a
35. Among the following, which metal has the lowest melting point?
a) Gold
b) Silver
c) Mercury
d) Copper
Answer: c
36. The second most abundant element in the Sun, after hydrogen, is:
a) Helium
b) Neon
c) Argon
d) Oxygen
Answer: a
37. Which is the highest quality of hard coal?
a) Anthracite
b) Bituminous
c) Lignite
d) Peat
Answer: a
38. The noble gas used in cancer treatment is:
a) Helium
b) Argon
c) Krypton
d) Radon
Answer: d