Question

There are $3$ samples of hydrogen peroxide labelled $10$ vol., $15$ vol and $20$ vol. Half litre of each was mixed. Calculate volume strength of the new solution.

• A. 7.5
• B. 15.0
• C. 22.5
• D. 51.0

Answer 1

Answer: (B)

Normality $=\frac{\text{ Volumestrength }}{5.6}$

$N_1=\frac{10}{5.6},N_2=\frac{15}{5.6},N_3=\frac{20}{5.6}$

New normality $=\frac{N_1{V}_1+N_2{V}_2+N_3{V}_3}{V_1+V_2+V_3}$

$N=\frac{\left(\frac{10}{5.6}\times 0.5\right)+\left(\frac{15}{5.6}\times 0.5\right)+\left(\frac{20}{5.6}\times 0.5\right)}{0.5+0.5+0.5}$

On solving, $N=\frac{15}{5.6}$

New volume strength $=N\times 5.6=\frac{15}{5.6}\times 5.6=15$ vol