Question

Why can metals high up in the reactivity series not be obtained by reduction of their oxides by carbon ?

The metals produced by various reduction processes are not very pure. They contain impurities, which must be removed to obtain pure metals. The most widely used method for refining impure metals is electrolytic refining.

Name the ore of mercury and state the form in which it is found in nature. Write the chemical equations along with the condition required for the reactions involved in the extraction of mercury from its ore.

Assertion (A) : The extraction of metals from their sulphide ores cannot take place without roasting of the ore. Reason (R) : Roasting converts sulphide ores directly into metals.