9702 · 14.3
Specific heat capacity and specific latent heat
When you add energy to a substance, it can either make it hotter (increasing kinetic energy) or change its state (increasing potential energy). This lesson explores how much energy is needed for each process.
Need to know
What you need to know
- 14.3 Specific heat capacity and specific latent heat.
- Recall the definition of specific heat capacity from IGCSE / SPM.
- The SI unit for specific heat capacity is J kg -1 K -1 or J kg -1 o C -1.
- The specific heat capacity tells us how much a substance can “absorb” thermal energy before its temperature increases.
- E.g., a metallic substance like copper has less heat capacity than wood. If both substances are exposed to heat simultaneously, the copper will have a higher temperature than the wood.
- Typically, a substance with a high c, will heat up or cool down slower .
Explanation
Energy's Two Faces: Heating Up vs. Melting Down
- Measure Mass: How much substance do you have?
- Heat It Up: Add energy, either to raise temperature or change state.
- Track Change: Observe temperature change or mass of substance that changes state.
- Calculate: Use specific formulas to find energy absorbed or released.