Question

Question 47
A metal that exists as a liquid at room temperature is obtained by heating its sulphide in the presence of air. Identify the metal and its ore and give the reaction involved.

Answer 1

Metals that are less reactive in nature are usually obtained by heating their sulphides in the air.

Mercury is the only metal that exists as a liquid at room temperature. It is obtained by heating cinnabar ($\text{HgS}$), the sulphide ore of mercury. The reactions are as follows:

$2\text{HgS(s)}+3{\text{O}}_2\stackrel{\text{Heat}}{\to }2\text{HgO(s)}+2{\text{SO}}_2\text{(g)}2\text{HgO(s)}\stackrel{\text{Heat}}{\to }2\text{Hg(l)}+{\text{O}}_2\text{(g)}$

Since, addition of an external reducing agent is not required, hence this process is also known as self-reduction.