Question

The approximate mass of $H_2{O}_2$ present in 200 mL of 100 volume $H_2{O}_2$ in grams is:

• A. 3
• B. 30
• C. 60
• D. 6

Answer 1

Answer: (C)

60

Volume strength refers to the volume of oxygen gas liberated from one volume of $H_2{O}_2$ solution (at 0°C and 1 atm.).

The volume of oxygen gas released is 100 ml for 1 ml of $H_2{O}_2$.

Since $H_2{O}_2$ is 200 ml so total volume liberated is 20 litres.

1 mol of oxygen is $22.4l$

So moles of oxygen = $\frac{20}{22.4}=0.89$

Since 2 moles of $H_2{O}_2$ produces 1 mol of oxygen so moles of hydrogen peroxide is 1.78

So, approximate mass is 60.71 $\simeq$ 60.