Question

Volume of 0.1 M $KMn{O}_4$, required to oxidise completely 50 ml of 0.5 M ferrous oxalate solution in acidic medium will be:

• A. $100$ mL
• B. $120$ mL
• C. $150$ mL
• D. $200$ mL

Answer 1

The correct option is A $100$ mL

In acidic medium, $M{n}^{+7}⟶M{n}^{+2}$

$n{f}_1=5$

$C_2{O}_4^{+2}=C{O}_2$

$2\times C^{+3}⟶C^{+4}$

$n{f}_2=2\times 1=2$

Thus by using equation,$\left(KMn{O}_4\right)n_1\times n{f}_1=n_{2}n{f}_2\left(Fe{C}_2{O}_4\right)$

$M_1{V}_1\times n{f}_1=M_2{V}_2\times n{f}_2$ as $n=M\times V$

$0.1M\times V_1\times 5=0.5M\times 50ml\times 2$ $(n_2\text{moles}=molarity(M)\times volume(V\left)\right)$

$V_1=100ml$