Thermochemistry: Determination of Heat Capacity of Calorimeter

What is the purpose of determining the heat capacity of a calorimeter?

A. To measure the temperature change of the substance
B. To calculate the heat gained by the substance
C. To raise the temperature of the calorimeter by 1 degree Celsius
D. To measure the heat changes in chemical reactions

Answer:

The purpose of determining the heat capacity of a calorimeter is to measure the heat changes in chemical reactions.

The heat capacity of a calorimeter is the amount of heat required to raise the temperature of the calorimeter by 1 degree Celsius. In the experiment of determining the heat capacity of a coffee cup calorimeter, the initial temperature of the water in the calorimeter is 23.5°C. The calorimeter is stirred and left for 5 minutes to ensure uniform temperature distribution.

To determine the heat capacity of the calorimeter, a known quantity of a substance with a known heat capacity, such as copper or aluminum, is used. The substance is heated to a known temperature and then transferred to the calorimeter. The temperature change of the substance and the calorimeter is measured using a thermometer.

By calculating the heat gained by the substance and the temperature change of both the substance and the calorimeter, the heat capacity of the calorimeter can be determined. This calculation is essential for accurately measuring the heat of reaction in subsequent experiments, as the heat capacity of the calorimeter is a crucial factor in these measurements.