The enthalpy change for the reaction between hydrochloric acid and sodium hydroxide is -56 kJ mol¹. Therefore
a)the reaction is exothermic and the temperature rises.
b)the reaction is exothermic and the temperature falls.
C )the reaction is endothermic and the temperature rises.
Ꭰ) the reaction is endothermic and the temperature falls.
a) the reaction is exothermic and the temperature rises.
The correct answer is:
a) The reaction is exothermic and the temperature rises.
Enthalpy change is a measure of the heat energy released or absorbed in a chemical reaction. A negative enthalpy change (-56 kJ mol⁻¹ in this case) indicates that the reaction is exothermic, meaning it releases heat to the surroundings. As a result, the temperature of the system would rise.
To determine the correct answer, we need to understand the relationship between enthalpy change and the temperature of a reaction. Enthalpy change refers to the amount of heat energy absorbed or released during a chemical reaction.
If the enthalpy change for a reaction is negative (-), it means the reaction is exothermic. An exothermic reaction releases heat energy into its surroundings. Conversely, if the enthalpy change is positive (+), the reaction is endothermic, meaning it absorbs heat energy from its surroundings.
In this case, the enthalpy change is -56 kJ mol¹, indicating that the reaction is exothermic since it has a negative sign. Therefore, options (a) and (b), which state that the reaction is exothermic, are the possible correct answers. However, to determine whether the temperature rises or falls, we need additional information.
Typically, an exothermic reaction results in a temperature rise, as it releases heat energy into the surroundings. On the other hand, an endothermic reaction absorbs heat energy, causing a temperature drop.
Without further information, we cannot definitively determine whether the temperature rises or falls. Therefore, the correct answer would be either option (a) or option (b), as it depends on the specific conditions of the reaction.