Question

What will be the mass of oxygen liberated by decomposition of 200 mL hydrogen peroxide solution with a strength of 34 g per litre ?
A. `25.5 g`
B. `3.0 g`
C. `3.2 g`
D. `4.2 g`

Answer 1

Correct Answer - C
Strength of the solution = 34 g/L
1 L of the solution contains 34 g of `H_(2)O_(2)`
200 mL of the solution contains `(34)/(1000)xx200=6.8 g` of `H_(2)O_(2)`
`underset(2xx34 g)(2H_(2)O_(2))to 2H_(2)O+underset(32 g)(O_(2))`
68 g of `H_(2)O_(2)` gives 32 g of `O_(2)`
6.8 g of `H_(2)O_(2)` gives `= (32)/(68)xx6.8=3.2g` of `O_(2)`