According to the following reaction, how many grams of hydrogen peroxide (H2O2) are needed to form 32.0 grams of oxygen gas?

The answer to your question is 34 g of H₂O₂    

Explanation:

Data

mass of H₂O₂ = ?

mass of O₂ = 32 g

Process

1.- Write the balanced chemical reaction

                   H₂O₂  ⇒   H₂  +  O₂

2.- Calculate the molar mass of H₂O₂ and O₂

Molar mass H₂O₂ = (1 x 2) + (16 x 2) = 34 g

Molar mass of O₂ = 2 x 16 = 32 g

3.- Use proportions to calculate the mass of O₂

                    34g of H₂O₂ 32g of O₂

                     x                   32g of O₂

                          x = (32 x 34) / 32

                          x = 34 g of H₂O₂