3.2.2 Temperature Changes in a System and Specific Heat Capacity

In this lesson, we will explore how the temperature of a system changes when it is heated, and how specific heat capacityAmount of heat energy required to increase the temperature of one unit of mass of a substance by one unit of temperature. plays a role in this process. We will discuss the factors that influence temperature changes, the equation that describes the relationship, and the concept of specific heat capacity.

Temperature Changes in a System

When energy is supplied to a system, such as through heating, the temperature of the system tends to increase. Factors affecting temperature change include:

• Mass: The mass of the substance being heated influences the amount of energy required to raise its temperature.
• Type of Material: Different materials have different abilities to absorb and retain heat, affecting the temperature change.
• Energy Input: The amount of energy supplied to the system determines the extent of the temperature increase.

The change in thermal energy (∆E) of a system is given by the equation:

∆E = m × c × ∆θ

Variables:

• ∆E = Change in thermal energy in joules, J
• m = Mass of the substance being heated in kilograms, kg
• c = Specific heat capacity in joules per kilogram per degree Celsius, J/kg °C
• ∆θ = Temperature change in degrees Celsius (°C)

Specific Heat Capacity

The specific heat capacity of a substance is the amount of energy required to raise the temperature of one kilogram of the substance by one degree Celsius

• Heat Absorption: Substances with high specific heat capacities require more energy to raise their temperature compared to substances with low specific heat capacities.
• Heat Retention: Substances with high specific heat capacities also tend to retain heat for longer periods, making them effective thermal storage materials.

Conclusion

We explored temperature changes in a system and the concept of specific heat capacity. Temperature changes depend on the mass of the substance, the type of material, and the energy input to the system. The equation ∆E = m × c × ∆θ describes the relationship between thermal energy, mass, specific heat capacity, and temperature change. Specific heat capacity represents the amount of energy required to raise the temperature of a substance per unit mass.