A 25.0 g sample of nitrogen reacts with 4.02 g of hydrogen to form ammonia (NH3) in the equation N2 + 3 H2 = 2 NH3 If ammonia is the only product, what is the mass of ammonia formed?

Mass = 22.1 g

Explanation:

Given data:

Mass of nitrogen = 25.0 g

Mass of hydrogen = 4.02 g

Mass of ammonia formed = ?

Solution:

Chemical equation:

N₂ + 3H₂     →     2NH₃

Number of moles of nitrogen:

Number of moles = mass/molar mass

Number of moles = 25.0 g/ 28 g/mol

Number of moles = 0.89 mol

Number of moles of nitrogen:

Number of moles = mass/molar mass

Number of moles = 4.02 g/ 2 g/mol

Number of moles =2.01 mol

now we will compare the moles of nitrogen and hydrogen with ammonia.

                H₂         :       NH₃

                  3          :         2

                  2.01     :        2/3×2.01 = 1.3 mol

                 N₂         :       NH₃

                   1          :         2

                 0.89     :        2/1×0.89 = 1.78 mol

hydrogen produced less number of moles of ammonia it will act ae limiting reactant.

Mass of ammonia:

Mass = number of moles × molar mass

Mass = 1.3 mol × 17 g/mol

Mass = 22.1 g