Metals and Non-metals
NCERT Exemplar Problems
MCQ Part 4
Question 28: Which among the following alloys contain mercury as one of its constituents?
- Stainless steel
- Zinc amalgam
Answer: (d) Zinc amalgam
Explanation: Amalgam is a mixture of mercury and any other metal.
Question 29: Reaction between X and Y, forms compound Z. X loses electron and Y gains electron. Which of the following properties is not shown by Z?
- Has high melting point
- Has low melting point
- Conducts electricity in molten state
- Occurs as solid
Answer: (b) Has low melting point
Explanation: Z is an ionic compound because it is formed by give and take of electrons. We know that ionic compounds are found as solid, have high melting point and conduct electricity in molten state.
Question 30: The electronic configurations of three elements X, Y and Z are X — 2, 8; Y — 2, 8, 7 and Z — 2, 8, 2. Which of the following is correct?
- X is a metal
- Y is a metal
- Z is a non-metal
- Y is a non-metal and Z is a metal
Answer: (d) Y is a non-metal and Z is a metal
Explanation: X is noble gas because it has 8 electrons in outermost shell. Y is a non-metal because it can gain one electron to complete octet. Z is a metal because it can donate 2 electrons to complete octet.
Question 31: Although metals form basic oxides, which of the following metals form an amphoteric oxide?
Answer: (c) Al
Question 32: Generally, non-metals are not conductors of electricity. Which of the following is a good conductor of electricity?
Answer: (b) Graphite
Question 33: Electrical wires have a coating of an insulting material. The material, generally used is
- All can be used
Answer: (c) PVC
Question 34: Which of the following non-metals is a liquid?
Answer: (b) Bromine
Question 35: Which of the following can undergo a chemical reaction?
- MgSO4 + Fe
- ZnSO4 + Fe
- MgSO4 + Pb
- CuSO4 + Fe
Answer: (d) CuSO4 + Fe
Explanation: Iron will displace copper from copper sulphate because it is more reactive than copper.
Question 36: Which one of the following figures correctly describes the process of electrolytic refining?
Explanation: Both figures (b) and (c) appear to be correct. But as per convention, anode should be shown on RHS. So, (c) is the correct answer. In both the cases, copper ions are liberating from anode and getting deposited at cathode.