Ammonia is formed from the reactants nitrogen and hydrogen in presence of a catalyst under suitable conditions. Assuming all volumes are measured in litres at s.t.p. Calculate the volume of ammonia formed if only 10% conversion has taken place.

[By Lussac’s law]

N₂      +     3H₂    →     2NH₃

1 vol    :    3 vol    →     2 vol

1 lit      :    3 lit     →     2 lit

To calculate the volume of ammonia formed when only 10% conversion takes place,

∴ 10 % of 2 lit = 10\over 100 ×2 = 0.2 lit

Hence, volume of ammonia formed is 0.2 lit or 20% or 1/5th of vol of N₂ and H₂