20 volume `H_(2)O_(2)` solution has a strength of about

Answer

6.07

Explanation

20 volumes of `H_(2)O_(2)` means 20 litres of oxygen is obtained at STP by the decomposition of 1 litre `H_2O_2` solution.
`underset("2 mole 68 g")(2H_(2)O_(2)) to 2H_(2)O + underset("1 mole 22.4 Litre at STP")(O_(2))`
`=68/22.4 xx 20 = 60.7g H_(2)O_(2)`
`therefore 1000 mL` of `H_(2)O_(2)` solution contains `60.7 g H_(2)O_(2)`
100 mL ( = 100 g) solution contains `60.7/1000 xx 100`
`= 6.07 g H_(2)O_(2) = 6.07%`