H2O2(aq) + 2H2o(l) + O2(g)?

Question

What volume of O2(g) collected at 27 degrees C and 746 torr, would be generated by decomposition of 125g of a 50% by mass hydrogen peroxide solution?

Answer 1

Atomic weights: H=1 O=16 O2=32 H2O2=34 27C=300K

2H2O2 ===> 2H2O + O2

Let the solution be called S

125gS x 50gH2O2/100gS x 1molH2O2/34gH2O2 x 1molO2/2molH2O2 x 22.4LO2/1molO2 x 760torr/746torr x 300K/273K = 23 L O2