For the water-gas shift reaction :
`CO_(g)) + H_(2)O_((g)) does the amount of `H_2` in an equilibrium mixture increase or decrease when the temperature is increased? How does K change when the temperature is decreased?

Explanation

`DeltaH^@ = - 41.2 kJ`, it is an exothermic reaction with heat lost to the surrounding.
Reactant -q ` less heat `" "` more heat
If temperature is increased, equilibrium displaces towards the direction of less heat to minimise the stress. This is backward direction, hence amount of `H_2` decreases.
If temperature is decreased reaction displaces toward forward side, hence K increases.