Chemistry Exercises .. What mass in grams of hydrogen peroxide should be used

hello guys, i have finished this excersices but yet i am not sure if the procedure i used is correct, i thank you for your help

Hydrogen peroxide is the active ingredient in commercial products to lighten the hair. What mass
in grams of hydrogen peroxide should be used to produce 1.0 liters of oxygen gas at 25 C and l atm? the
equation for the reaction is:
H2O2 (aq) → O2 (g) + H2O

.. What amount of water (grams) should be diluted 80 ml of sulfuric acid solution of density 1.2
g / ml to 30% by weight, to ensure that the concentration is 10 wt% sulfuric acid (H 2SO4)?

2 H2O2 → O2 + 2 H2O

(1.0 L O2) x (273 / (25 + 273)) / (22.4 L/mol) x (2/1) x (34.0148 g H2O2/mol) =
2.8 g H2O2