Equilibrium Question 689
Question: In the manufacture of $ NH_3 $ by Haber’s process, the condition which would give maximum yield is $ N_2+3H_2 $ ⇌ $ 2NH_3+Q,kcal $ [NCERT 1978; EAMCET 1980; MNR 1987; AFMC 1999; CPMT 1983, 84, 86, 94; MP PMT 1999]
Options:
A) High temperature, high pressure and high concentrations of the reactants
B) High temperature, low pressure and low concentrations of the reactants
C) Low temperature and high pressure
D) Low temperature, low pressure and low concentration of $ H_2 $
Show Answer
Answer:
Correct Answer: C
Solution:
The manufacture of ammonia by Haber’s process is an exothermic reaction. According to Le Chatelier’s principle maximum yield of an exothermic reaction can be obtained at low temperatures. There are 4 molecules on reactant side and 2 on product side. According to Le Chatelier’s principle if you increase the pressure the system will respond by favouring the reaction which produces fewer molecules. So the maximum yield of ammonia will be obtained at high pressure and low temperature
