posted by Adulkarim .
Calculate the volume of oxygen starndad temperature and pressure which theoretically could be obtained from the 50cm3 of the solution of hydrogen peroxide containing 68g/dm3
68 g x *50 cc/1000 dm^3 = ? g H2O2.
mols H2O2 = grams/molar mass.
Then you know 1 mol occupies 22.4L a STP.