Question

$20mL$ of $0.02M{K}_{2}C{r}_2{O}_7$ solution is used for the titration of $10mL$ of $F{e}^{2+}$ solution in the acidic medium.
The molarity of $F{e}^{2+}$ solution is_____ $\times 10^{-2}M$. (Nearest Integer)

Answer 1

Answer: 24

Eq. of $K_{2}C{r}_2{O}_7=$ Eq. of $F{e}^{2+}$
$\Rightarrow (\text{ Molarity }\times \text{ volume }\times \text{ n.f) of }{K}_{2}C{r}_2{O}_7$
$=(\text{ molarity }\times \text{ volume }\times \text{ n.f })\text{ of }F{e}^{2+}$
$\Rightarrow 0.02\times 20\times 6=M\times 10\times 1$
$\Rightarrow M=0.24$
$\Rightarrow \text{ Molarity }=24\times 10^{-2}$