Question

If the pressure in a reaction vessel for the following reaction is increased by decreasing the volume, what will happen to the concentrations of CO and CO2? `H_2O (g)+ CO_2 (g) rightleftharpoons H_2 (g)+ CO_2 (g)+heat`

(a) both the [CO] and `[CO_2]` will decrease
(b) neither the [CO] nor the `[CO_2]` will change
(c) the [CO] will decrease and the `[CO_2]` will increase
(d) both the [CO] and `[CO_2]` will increase

Answer 1

For `H_2O(g) + CO(g) rightleftharpoonsH_2(g) + CO_2(g) + Delta`

Explanation:

You have decreased the VOLUME....the concentrations of both reactants, and products INCREASE....and so `[CO]` AND `[CO_2]` will INCREASE....`"option D"` is the answer I would give.

And you don't even have to consider how the equilibrium will evolve (the position of equilibrium should remain unchanged in this scenario).