What mass of hydrogen peroxide is present in 2.5 litre solution of 5 M strength? Calculate the volume of oxygen at STP liberated upon complete decomposition of `500 cm^3` of the above solution.

Explanation

Calculation of mass of `H_2O_2`
Mol of `H_2O_2` in `2.5L` of `H_2O_2` solution`=V_((L)) xx M = 2.5 xx 5 = 12.5 `mols
`therefore ` Mass of `H_2O_2` present `= 12.5 xx GMM = 12.5 xx 34 = 425g `
Calculation of Volume of `O_2` liberated at STP
Mol of `H_2O_2` in `500 cm^3` of solution `= 500 xx 10^(-3) xx 5 = 2.5 mol `
2 mol of `H_2O_2` give `O_2 = 22.4 L` at ST
`2.5 `mol of `H_2O_2` give `O_2 = (22.4 xx 2.5)/2 = 28.0L `