Answer: The percentage yield of water is 9.5 %
Step-by-step explanation:
We are given:
Moles of hydrogen = 14 moles
Moles of oxygen = 10 moles
The chemical equation for the formation of water from hydrogen and oxygen follows:

By Stoichiometry of the reaction:
2 moles of hydrogen gas reacts with 1 mole of oxygen gas
So, 14 moles of hydrogen gas will react with =
of oxygen gas
As, given amount of oxygen gas is more than the required amount. So, it is considered as an excess reagent
Thus, hydrogen gas is considered as a limiting reagent because it limits the formation of product.
By Stoichiometry of the reaction:
2 moles of hydrogen gas produces 2 moles of water
So, 14 moles of hydrogen gas will produce =
of water
To calculate the percentage yield of water, we use the equation:

Experimental yield of water = 1.33 moles
Theoretical yield of water = 14 moles
Putting values in above equation, we get:

Hence, the percent yield of the water is 9.5 %.