Answer to Question #111922 in General Chemistry for Joyce

Question

1. One of the reactions involved in the production of nitric acid is:



4NH3(g) + 5O2(g) ⇌ 4NO(g) + 6H2O(g) + heat



For maximum yield of NO(g) at equilibrium, this reaction should be carried out:

Question 1 options:

at high temperature and low pressure.


at high temperature and high pressure.


at low temperature and high pressure.


at low temperature and high pressure.

Answer 1

We use Le Chatelier's Principle here,

As NO is formed in the product side, increasing its yield means we need the reaction to go in forward direction.

Forward reaction is characterized by increase in pressure (as number of gaseous moles increase) and increase in temperature (as heat is released).

Thus, decrease in pressure and decrease in temperature favors forward reaction.

For maximum yield of NO(g) at equilibrium, this reaction should be carried out:

at low temperature and low pressure.