Question

‘X’ melts at low temperature and is a bad conductor of electricity in both liquid and solid state. X is:

• A. Mercury
• B. Silicon Carbide
• C. Zinc Sulphide
• D. Carbon Tetrachloride

Answer 1

The correct option is D

Carbon Tetrachloride

Explanation for correct option:

(d) $\mathrm{Carbon}\mathrm{Tetrachloride}\left({\mathrm{CCl}}_4\right)$

• The melting point of carbon tetrachloride is −22.92oC.
• The dipole moment is zero. Hence, it is a non-polar compound. As there is no charge separation in the molecule, therefore, this compound is a bad conductor of electricity in solid as well as in the liquid state.
• So it melts at low temperatures and is a bad conductor of electricity in both liquid and solid-state.

Explanation for incorrect options:

• (a) $\mathrm{Mercury}\left(\mathrm{Hg}\right)$ is in liquid form and it is the conductor of electricity.
• (b) $\mathrm{Silicon}\mathrm{Carbide}\left(\mathrm{SiC}\right)$ is a semi-conductor.
• (c) $\mathrm{Zinc}\mathrm{Sulphide}\left(\mathrm{ZnS}\right)$ us intrinsic semi-conductor.

Hence, option (d) is correct.