Gaseous hydrogen and oxygen can be prepared in the laboratory from the decomposition of gaseous water. The equation for the reaction is

2H2O(g)⟶2H2(g)+O2(g)

Calculate how many grams of O2(g) can be produced from 58.9 g H2O(g).

Mass of oxygen = 52.32 g

Explanation:

Given data:

Mass of water = 58.9 g

Mass of oxygen produced = ?

Solution:

Chemical equation:

2H₂O  →   2H₂ + O₂

Number of moles of water:

Number of moles = mass/ molar mass

Number of moles = 58.9 g/ 18 g/mol

Number of moles = 3.27 mol

Now we will compare the moles of water with oxygen from balance chemical equation.

                  H₂O           :            O₂

                     2             :            1

                3.27             :           1/2×3.27 = 1.635 mol

Mass of oxygen produced:

Mass = number of moles × molar mass

Mass = 1.635 mol × 32 g/mol

Mass = 52.32 g