Video 1. Adding a solution to a coffee cup calorimeter equipped with a glass thermometer and manual stir rod.
Video 2. Adding a solution to a coffee cup calorimeter equipped with a thermocouple probe and magnetic stirrer.
Typically, one of the reactant solutions is added to the calorimeter and allowed to reach thermal equilibrium with the calorimeter. (It is often advantageous to place the reactant with the larger volume in the calorimeter first. Why?)
Thermal equilibrium is reached when, after recording the temperature at regular time intervals, there is no longer an observed temperature change in the reaction mixture (approximately 3-5 mins).
Next, measure the temperature of the second substance to be
added to the calorimeter. Remove the lid from the calorimeter, and quickly but carefully pour the second substance into the cup; immediately replace
the lid, record the temperature of the mixture, and begin stirring
the substances together. The substances should be stirred continuously.
Record the temperature of the system at regular, frequent intervals
until no further temperature change is observed.
Don't forget: The temperature
in the calorimeter should be observed at frequent intervals.
