Question

Hydrogen gas and chlorine gas react according to the following equation H2(g) + Cl2(g) <------> 2HCl(g) + Energy

Hydrogen gas and chlorine gas are placed in a sealed container and are allowed to reach equilibrium. What effect will heating the system have?

Answer 1

According to Le Chatelier’s principle when a stress is applied to a system in equilibrium the equilibrium will move in a direction to minimize the effect of the applied stress.

The given reaction is an exothermic reaction as heat is released. So applying more heat to an exothermic reaction will cause the reaction to move in the direction where heat is not released. Thus the equilibrium will shift in the direction of the reactants.

Answer 2

H2(g) + Cl2(g) <------> 2HCl(g) + Energy

Because this reaction is going with release of heat, so adding more heat will shift this reaction toward the side that is going to remove this heat, to the reactant side.

H2(g) + Cl2(g) <------> 2HCl(g) + Energy
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