AQA GCSE FOUNDATION Physics: Investigating Specific Heat Capacity

Investigating Specific Heat Capacity: A Practical Guide

This tutorial will guide you through an experiment to investigate the specific heat capacity of different materials. This experiment will involve measuring the energy required to raise the temperature of different materials and then calculating their specific heat capacity.

Understanding Specific Heat Capacity

Specific heat capacity (c) is a measure of the amount of energy required to raise the temperature of 1 gram of a substance by 1 degree Celsius (or 1 Kelvin). Different materials have different specific heat capacities.

• High specific heat capacity: A material with a high specific heat capacity requires a lot of energy to raise its temperature. Water is a good example. It takes a lot of energy to heat up water, which is why it's used in many cooling systems.
• Low specific heat capacity: A material with a low specific heat capacity requires less energy to raise its temperature. Metals like copper and aluminum have low specific heat capacities, making them good for cooking pots and pans.

The Experiment

Materials:

• Electric heater
• Beaker or container
• Thermometer
• Balance scale
• Different materials (e.g., water, sand, metal blocks)
• Power supply
• Stopwatch
• Calculator

Procedure:

1. Measure the mass of the material. Use the balance scale to accurately determine the mass (m) of the material you'll be heating.
2. Set up the heater. Connect the electric heater to a power supply and ensure it's working properly.
3. Record the initial temperature. Use the thermometer to record the initial temperature (T?) of the material.
4. Heat the material. Turn on the electric heater and immerse it in the material. Start the stopwatch simultaneously.
5. Monitor the temperature change. Observe the temperature rise as the material heats up. Record the temperature (T?) at regular intervals (e.g., every 30 seconds).
6. Calculate the energy transfer. To calculate the energy (E) transferred to the material, you'll need to know the power output of the heater (P) and the time (t) the heater was on. Use the formula: E = P x t.
7. Calculate the specific heat capacity. Using the measured values and the following formula, calculate the specific heat capacity (c) of the material:

c = E / (m * ?T)

where: * ?T = (T? - T?) is the change in temperature

1. Repeat with different materials. Repeat the experiment with different materials to compare their specific heat capacities.

Analyzing the Results

• Compare specific heat capacities: Compare the calculated specific heat capacities of the different materials. Which material required the most energy to raise its temperature? Which material required the least?
• Explain the differences: Use your understanding of specific heat capacity to explain the differences in energy requirements for each material.
• Real-world applications: Discuss how the concept of specific heat capacity applies to real-world situations like cooking, weather patterns, or the design of thermal insulation.

Safety Precautions

• Always handle the electric heater with care. Be cautious of any potential heat sources and avoid touching the heater directly while it's on.
• Use a heat-resistant container to hold the material.
• Always wear appropriate safety gear (e.g., gloves, goggles) if working with potentially hazardous materials.

By following these steps and analyzing your results, you'll gain a deeper understanding of specific heat capacity and its importance in the transfer of thermal energy.