Question

$Pb$ and $Sn$ are extracted from their chief ore respectively by

• A. Self reduction and carbon reduction
• B. Electrolysis and self-reduction
• C. Self reduction and electrolysis
• D. Carbon reduction and self-reduction

Answer 1

The correct option is A Self reduction and carbon reduction

$PbO$ and $PbS{O}_4$ get reduced by $PbS$ itself which is already present in mixture. Since, the reduction took place by mixture itself, hence it is known as self-reduction.
$2PbO+PbS\stackrel{\Delta }{\to }3Pb+S{O}_2\uparrow$
$PbS{O}_4+PbS\stackrel{\Delta }{\to }2Pb+2S{O}_2\uparrow$
$Sn{O}_2+C\to Sn+C{O}_2$