Question

$3.4$ g sample of $H_2{O}_2$ solution containing $x\%$ $H_2{O}_2$ by weight requires $x$ mL of $KMn{O}_4$ solution for complete oxidation under acidic condition. The normality of $KMn{O}_4$ solution is :

• A. $1N$
• B. $2N$
• C. $3N$
• D. $0.5N$

Answer 1

Answer: (B)

$2N$

$100$ g of $H_2{O}_2$ sample solution contains $x$ g of $H_2{O}_2$.

$3.4$ g of solution contains $=\frac{x}{100}\times 3.4$

Weight of $H_2{O}_2=\frac{3.4x}{100}$

Equivalent weight of $H_2{O}_2=\frac{3.4x}{100}\times \frac{1}{17}$

Milliequivalents of $H_2{O}_2=\frac{3.4x}{100\times 17}\times 1000=\frac{34x}{17}=2x$

Milliequivalents of $KMn{O}_4=x\times N$
$\therefore x\times N=2x$
$⟹N=2$

Hence, the normality of $KMn{O}_4$ solution is $2N$.