International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

In an exothermic reaction, heat is released as a product. According to Le Chatelier's Principle, if the temperature of a system at equilibrium is increased, the system will respond by favoring the endothermic direction of the reaction in order to counteract the change.

For exothermic reactions, this means that increasing the temperature will shift the equilibrium position to the left, towards the reactants, as the system seeks to absorb the added heat. By shifting to the left, the system reduces the concentration of products and partially reverts to the reactants, effectively using up some of the added heat.

The other choices suggest that the equilibrium either shifts to the right or remains unchanged, both of which do not align with Le Chatelier's Principle in the context of an exothermic reaction when temperature is increased. The option stating that the reaction ceases is also incorrect, as the reaction does not stop but instead adjusts the equilibrium position in response to the temperature change.