Hc-10 Heat Capacity

Aim

To demonstrate the heat capacity of two different metals. (Aluminium and Copper)

Apparatus

  • Pasco 850 Universal Interface
  • Laptop Computer
  • Capstone Software
  • Pasco Digital Thermometers x2
  • Polystyrene Cups (200ml) x2
  • Polystyrene Base
  • 1L Beaker of Water-Room Temperature
  • 1L Beaker of Boiling Water
  • IEC Hot Plate
  • 40g Copper Block
  • 40g Aluminium Block

Diagrams

Heat Capacity 1

Setup

Heat Capacity Graph

Temperature (Al &  Cu)  v  Time

Description

Two polystyrene cups are placed on polystyrene base for maximum thermal insulation. A Pasco Digital Thermometer is securely placed in each cup so that it won’t make contact with the copper and aluminium blocks, when the blocks are placed in the cups. The Pasco Digital Thermometers are connected to Pasco 850 Universal Interface, which is connected to the Laptop Computer. The Aluminium and Coppers blocks are placed into the beaker of boiling water on the Hotplate, allowing a couple of minutes for the blocks to reach 100°C. Meanwhile 200ml of room temperature water is placed into each of the polystyrene cups. Two graphs of Temperature versus Time are configured on the Capstone Software. Start recording the Capstone Graph. The temperature of the water in the polystyrene cups should read around 24°C room temperature.

The Aluminium and Copper blocks which should be 100°C  at this stage. The blocks are simultaneously placed into different cups, making sure they don’t make contact with the thermometer. The temperature of the water in the different cups are observed on the Capstone Graphs.

The temperature of the water with the Aluminium Block will reach a higher temperature than the temperature of the water with the Copper Block by around 2°C, over period of a few minutes.

Heat Capacity is given by the equation CH=Q/ΔT units J/°C

Where Q is the energy supplied to heating the block                                                   ΔT is the rise in temperature

Specific Heat Capacity is given by the equation CS=Q/m.ΔT units J/g°C

Where Q is the energy supplied to heating the block ΔT is the rise in temperature m is the mass of the block

The Specific Heat of Aluminium, Copper & Water are 0.900 J/g°C, 0.385 J/g°C and 4.186 J/g°C respectively. We means the copper requires less energy to heat up 1°C than aluminium, which requires less energy than water.

This demonstration shows the Heat Capacity of the blocks of Aluminium and Copper in reverse. Where heat is given up to water from the blocks. The specific heat of water is a known quantity, the specific heat of Aluminium and Copper can be calculated by the above equations since we know the temperature difference of the water.

What we can observe from this demonstration is the higher the Specific Heat of a substance the more energy is required to heat up that substance, also has greater ability to store heat energy. While the lower the Specific Heat of a substance the less energy is required to heat up that substance, also has a greater ability to dissipate heat.