Question

The extraction principle used in extraction of a metal '$M$' can be represented as follows
$MS +2 O _{2} \rightarrow MSO _{4} $
$MSO _{4}+ MS \rightarrow 2 M +2 SO _{2}$
The metal '$M$' is

• A. $Mg$
• B. $Pb$
• C. $Sn$
• D. $Fe$

Answer 1

Answer: (B)

It is a case of self reduction.
The concentrated galena (PbS) is partially oxidised by adjusting the air supply.
$\text{PbS} + 2 \text{O}_{2} \rightarrow \text{PbSO}_{4}$
The temperature is raised, air supply reduced and fresh galena (PbS) added.
$\text{PbS} + \text{PbSO}_{4} \rightarrow 2 \text{Pb} + 2 \text{SO}_{2} \uparrow$