Question

$F{e}_2{O}_3,Sn{O}_2,PbS,MgC{l}_2,HgS,ZnS,A{l}_2{O}_3,A{g}_{2}S,C{u}_{2}S$
Consider given ores and calculate the value of expression $\left(\frac{Q+R}{P\times S}\right)$, where,
P = Number of ores from which the metal is commercially extracted by Hydrometallurgy.
Q = Number of ores from which the metal is commercially extracted by Self-reduction.
R = Number of ores from which the metal is commercially extracted by carbon reduction.
S = Number of ores from which metal is commercially extracted by electrolyitc reduction.

Answer 1

$P=A{g}_{2}S,$
$Q=C{u}_{2}S,HgS,PbS$
$R=F{e}_2{O}_3,Sn{O}_2,ZnS$
$S=MgC{l}_2,A{l}_2{O}_3$

Hence, P = 1, Q = 3, R = 3 and S = 2
then,
$\left(\frac{3+3}{1\times 2}\right)=3$