Le Chatelier's Principle; Temperature

Question

Given the following reaction:

Hb(CO)₄(aq) + 4 O₂(g) <--> Hb(O₂)₄ (aq) + 4 CO(g)                ΔH= -123.5 kJ

If the temperature of the reaction is increased, the reaction will shift to the ___ to restore equilibrium.

A. Left

B. Right

Answer 1

The sign of ∆H is negative, meaning the reaction is exothermic. This means the reaction gives off heat and so heat can be viewed as a product (right side). You can write the equation as

Hb(CO)₄(aq) + 4 O₂(g) <--> Hb(O₂)₄ (aq) + 4 CO(g) + HEAT

If the temperature of the reaction is increased, that's the same as increasing a product and so the reaction will shift to the left (reactant side) to restore the equilibrium. Answer A.