Question

 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 reactions involved. 

Answer 1

Mercury is the metal which exists as a liquid at room temperature. It can be obtained by heating the sulphide ore in the presence of air. The process is known as roasting. The chemical reactions involved are :
`2HgS(s) + 3O_(2)(g) overset("heat")rarr2HgO(s) + 2SO(g)`
`2HgO(s) overset("heat")rarr 2Hg(l) + O_(2)(g)`.