Metals and Non-metals NCERT Exemplar Problems
MCQ Part 1
Question 1: Which of the following property is generally not shown by metals?
- Electrical conduction
- Sonorous in nature
- Dullness
- Ductility
Answer: (c) Dullness
Explanation: Metals have a typical shine, known as metallic lustre.
Question 2: The ability of metals to be drawn into thin wire is known as
- Ductility
- Malleability
- Sonority
- Conductivity
Answer: (a) Ductility
Question 3: Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same?
- Good thermal conductivity
- Good electrical conductivity
- Ductility
- High melting point
- (i) and (ii)
- (i) and (iii)
- (ii) and (iii)
- (i) and (iv)
Answer: (d) (i) and (iv)
Explanation: Electrical conductivity has no role to play in heating of a cooking utensil. Malleability, rather than ductility is required to make thin sheet of metal. So, options (ii) and (iii) are easily ruled out.
Question 4: Which one of the following metals does not react with cold as well as hot water?
- Na
- Ca
- Mg
- Fe
Answer: (d) Fe
Explanation: Iron reacts with steam but not with hot or cold water.
Question 5: Which of the following oxide(s) of iron would be obtained on prolonged reaction of iron with steam?
- FeO
- Fe2O3
- Fe3O4
- Fe2O3 and Fe3O4
Answer: (c) Fe3O4
Explanation: Refer to equation given in explanation of previous question.
Question 6: What happens when calcium is treated with water?
- It does not react with water
- It reacts violently with water
- It reacts less violently with water
- Bubbles of hydrogen gas formed stick to the surface of calcium
- (i) and (iv)
- (ii) and (iii)
- (i) and (ii)
- (iii) and (iv)
Answer: (d) (iii) and (iv)
Explanation: Calcium hydroxide and hydrogen gas are formed when calcium reacts with water. This reaction is not as violent as reaction of sodium with water.
Ca + 2H2O → Ca(OH)2 + H2
Question 7: Generally metals react with acids to give salt and hydrogen gas. Which of the following acids does not give hydrogen gas on reacting with metals (except Mn and Mg)?
- H2SO4
- HCl
- HNO3
- All of these
Answer: (c) HNO3
Explanation: When nitric acid reacts with metal it does not produce hydrogen gas. Nitric acid is a strong oxidizing agent and hence it oxidizes the hydrogen gas to form water. Nitric acid itself gets reduced to form oxide of nitrogen (N2O, NO, NO2).
Question 8: The composition of aqua-regia is
- Dil.HCl : Conc. HNO3 − 3 : 1
- Conc.HCl : Dil. HNO3 − 3 : 1
- Conc.HCl : Conc.HNO3 − 3 : 1
- Dil.HCl : Dil.HNO3 − 3 : 1
Answer: (c) Conc. HCl : Conc. HNO3 − 3 : 1
Question 9: Which of the following are not ionic compounds?
- KCl
- HCl
- CCl4
- NaCl
- (i) and (ii)
- (ii) and (iii)
- (iii) and (iv)
- (i) and (iii)
Answer: (b) (ii) and (iii)
Explanation: These are covalent compounds.