Describe the procedure for measuring the enthalpy change of a reaction using a calorimeter.

To measure the enthalpy change, first, prepare a calorimeter by adding a known volume of water and measuring its initial temperature. Then, add the reactants to the calorimeter and stir. Record the highest or lowest temperature reached after the reaction has occurred. The enthalpy change can be calculated using the formula ΔH = - (m × c × ΔT) / n, where m is the mass of water, c is the specific heat capacity of water, ΔT is the change in temperature, and n is the number of moles of the limiting reactant. This answer is anchored to AS required practical activities.

To measure the enthalpy change, first, prepare a calorimeter by adding a known volume of water and measuring its initial temperature. Then, add the reactants to the calorimeter and stir. Record the highest or lowest temperature reached after the reaction has occurred. The enthalpy change can be calculated using the formula ΔH = - (m × c × ΔT) / n, where m is the mass of water, c is the specific heat capacity of water, ΔT is the change in temperature, and n is the number of moles of the limiting reactant. is the best answer because it directly supports the AQA A-Level Chemistry objective to required practical 2: measure an enthalpy change. This reasoning is anchored to AS required practical activities in AS practical skills and required practical activities, and it separates required practical from similar A-Level ideas rather than relying on a vague recall statement. Other options are weaker if they use the wrong evidence, calculation, mechanism, observation, unit, or conclusion for this subtopic.