6.4 Specific Heat Capacity

Question 1

Describe how energy is transferred as a kettle’s water heats up

Answer 1

In an electrical kettle, energy is transferred electrically from the mains to the thermal energy store of the kettle’s heating element. It is then transferred by heating to the thermal energy store of the water (the kinetic energy stores of the particles) - the water’s temperature rises

Question 2

What is specific heat capacity?

Answer 2

The specific heat capacity of a material is the energy required to raise one kilogram (kg) of the material by one degree Celsius (°C).

Question 3

What equipment do you need to find the specific heat capacity of a liquid?

Answer 3

• Joulemeter
• Electric heater
• Thermometer
• Liquid
• Insulating containing, e.g. polystyrene cup

Question 4

How do you find the specific heat capacity of a liquid or solid? (3)

Answer 4

• Make sure that the apparatus is set up correctly and used safely - e.g. make sure not to burn yourself when handling the heater and that there is no chance of the liquid spilling out of the polystyrene cup.
• Measure the temperature of the substance you’re investigating, then turn on the power. Keep an eye on the thermometer. When the temperature has increased by e.g. ten degrees, stop the experiment and record the energy on the joulemeter and the increase in temperature.
• Use your results to calculate the specific heat capacity of your substance. Repeat the whole experiment at least three times, then calculate an average specific heat capacity.

Question 5

When testing the specific heat capacity of a solid, what equipment do you need?

Answer 5

• Joulemeter
• Electric meter
• Thermometer
• Conducting gel between heating and cylinder to improve conduction (and so accuracy)
• Insulating container packed with cotton will