Question

$7.36$ g of a mixture of $KCl$ and $KI$ was dissolved in $H_{2}O$ to prepare $1$ litre solution. $25$ ml of this required $8.45$ ml of $0.2$ N $AgN{O}_3$.

What is the percentage of $KI$ in the mixture?

• A. $57.28$
• B. $47.28$
• C. $5.72$
• D. $49.12$

Answer 1

The correct option is A $57.28$

We have a mixture containing $KI+KCl$.

Gram equivalents of mixture $=$ Gram equivalents of $AgN{O}_3$.

Let, $x$ g be the weight of $KI$.

Then, the weight of $KCl$ will be $(7.36-x)$ g.

$(\frac{x}{166}+\frac{7.36-x}{74.5})=\frac{8.45\times 0.2\times 40}{1000}$

$\therefore$ On solving, we get $x=4.216$ g.

$\therefore$ Percentage of $KI=57.28\%$