Aim: To show that when Hot and Cold water are mixed, heat lost by hot water is equal to heat gained by cold water.
Theory: This Lab is done to demonstrate “the Law of Conservation of Energy”, which implies: - “the heat lost by one (1) substance must be equal to the heat gained by another substance within the system”. Apparatus: Two (2) similar Calorimeters: a Thermometer: a Measuring Cylinder: a Bunsen burner: a Tripod: an Asbestos Gauze Cork Mat.
* The tripod and Bunsen burner were set up as shown in fig. 1 * Using the measuring cylinder 50gm of water was measured and poured into (1) one calorimeter labeled A, and 100gm was also measured and poured into the other calorimeter labeled B. * The calorimeter containing the 50gm of water was set on the cork mat and its temperature recorded at 23o C. * The other calorimeter containing 100gm of water was placed on the tripod and the Bunsen burner lit. * The thermometer was placed into the calorimeter and the water heated to approximately 73oC. then removed from the heat and stirred until a temperature of 70o C was achieved. * When this temperature was achieved, the water in this calorimeter (B) was poured into the calorimeter containing the “cold water” (A). * They were then mixed and the maximum temperature recorded, with the use of the thermometer.
This procedure was repeated but in this instance the water in A was poured into B, the results were recorded in the table following
Results: Table 1 Heat loss by “Hot Water” | Mass of Hot water | 100gm | Temperature of hot water | 70o C | Temperature of Mixture | 39oC | T | 31o C | Quantity of Heat Loss | 13020 J | The Quantity of Heat Loss was calculated using: Q=MST.
Where: M=mass: S=specific heat capacity: T= the change in temperature.
Note: the specific heat capacity of water 4.2 Table 2 Heat Gained by ‘Cold Water’ | Mass of Cold Water | 50gm | Temperature