If all the H2O2 in 25mL of a 3% solution of H2O2 decomposed, calculate the

Question

diameter of a sphere that would contain the resulting O2 at 1 atm and 296K.

I understand how to do the problem if I have moles but I am not sure how to get moles. I thought n=0.075moles because 3% solution could mean 3M so 3 moles/ L and 0.025L

Answer 1

I believe this is 3% w/w which means 3g H2O2/100 g solution.
mols H2O2 = 3/molar mass H2O2 in 100 g solution.

2H2O2 ==> 2H2O + O2

Answer 2

Thanks!!