Answer: The mass of ammonia formed is 22.61 grams
Step-by-step explanation:
To calculate the number of moles, we use the equation:
.....(1)
Given mass of hydrogen gas = 4 g
Molar mass of hydrogen gas = 2 g/mol
Putting values in equation 1, we get:

Given mass of nitrogen gas = 30 g
Molar mass of nitrogen gas = 28 g/mol
Putting values in equation 1, we get:

The chemical equation for the formation of ammonia follows:

By Stoichiometry of the reaction:
3 moles of hydrogen gas reacts with 1 mole of nitrogen gas.
So, 2 moles of hydrogen gas will react with =
of nitrogen gas.
As, given amount of nitrogen 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:
3 moles of hydrogen gas produces 2 moles of ammonia
So, 2 moles of hydrogen gas will produce =
of ammonia
- Now, calculating the mass of ammonia from equation 1, we get:
Molar mass of ammonia = 17 g/mol
Moles of ammonia = 1.33 moles
Putting values in equation 1, we get:

Hence, the mass of ammonia formed is 22.61 grams