Question

nitrogen and hydrogen react to form ammonia. N2+3H2=2NH3. 12 dm3 of hydrogen reacted with excess nitrogen to form 2 dm3 of ammonia. what is the percentage yield of ammonia at room temperature and pressure

Answer 1

N2 + 3H2 ==> 2NH3

With gases one can take a shortcut and work the problem as if volume = mols.
12 dm3 H2 x (2 dm3 NH3/3 dm3 H2) = 8 dm3 NH3 if the yield were 100%. It formed 2 dm3; therefore,
%yield = (2/8)*100 = ?%.

Answer 2

75%