Question

How many liters of oxygen will be produced when 25.0 g of hydrogen peroxide reacts at STP?

Answer 1

`8.23 " L "O_2`

Explanation:

Given: `25.0 g` hydrogen peroxide at STP

hydrogen peroxide: `H_2O_2`

skeletal equation: `H_2O_2 (aq) -> H_2O + O_2 (g)`

balanced equation: `2H_2O_2 (aq) -> 2H_2O + O_2 (g)`

molar mass of `H_2O_2 = 2(1.008) + 2(15.999) = 34.014 g/("mol")`

From the balanced equation: `(1 mol O_2)/(2 mol H_2O_2)`

`25.0 cancel(g H_2O_2) xx (1 color(red)(cancel(mol H_2O_2)))/(34.014 cancel(g H_2O_2)) xx (1 color(blue)(cancel(mol O_2)))/(2 color(red)(cancel(mol H_2O_2))) xx (22.4 L O_2)/(1 color(blue)(cancel(mol O_2)))`

`= 8.23 " L "O_2`