Answer:
Mass = 18.36 g
Explanation:
Given data:
Mass of nitrogen = 15 g
Mass of hydrogen = 4 g
Mass of ammonia produced = ?
Solution:
Chemical equation:
N₂ + 3H₂    →    2NH₃
Number of moles of nitrogen:
Number of moles = mass/molar mass
Number of moles = 15 g/ 28 g/mol
Number of moles  = 0.54 mol
Number of moles of hydrogen:
Number of moles = mass/molar mass
Number of moles = 4 g/ 2 g/mol
Number of moles  = 2 mol
now we will compare the moles of ammonia with nitrogen and hydrogen.
          H₂       :       NH₃
           3       :       2
           2        :       2/3×2 = 1.3
           N₂       :       NH₃
           1        :       2
         0.54       :       2/1×0.54 = 1.08
less number of moles of ammonia are produced by nitrogen thus it is limiting reactant.
Mass of ammonia:
Mass = number of moles × molar mass
Mass = 1.08 mol × 17 g/mol
Mass = 18.36 g