Answer:
Measuring temperature is important in determining whether a change in enthalpy is exothermic or endothermic because it allows us to observe the direction of heat flow during a chemical reaction. Enthalpy is a measure of heat energy transferred during a chemical reaction, and is represented by the symbol "ΔH". During an exothermic reaction, heat is released and transferred from the system to the surroundings, resulting in a decrease in the temperature of the system. In contrast, during an endothermic reaction, heat is absorbed by the system from the surroundings, resulting in an increase in the temperature of the system. By measuring the temperature change of the system during a chemical reaction, we can determine whether the reaction is exothermic or endothermic. A decrease in temperature indicates an exothermic reaction, while an increase in temperature indicates an endothermic reaction. Therefore, measuring temperature is crucial in determining the direction of heat flow and whether a change in enthalpy is exothermic or endothermic.