Heat Capacity
Heat Capacity
Heat capacity describes how much heat energy a substance must absorb or release to change its temperature by a given amount. It is central to understanding how materials store and transfer thermal energy.
Specific Heat Capacity
The heat required to change the temperature of a mass by is:
Where:
- is the heat energy added (J)
- is the mass (kg)
- is the specific heat capacity of the material (J/kg·K)
- is the temperature change (K or °C — they are equivalent for differences)
Common Specific Heats
| Material | (J/kg·K) |
|---|---|
| Water | 4186 |
| Aluminium | 900 |
| Iron | 450 |
| Copper | 385 |
Water's unusually high specific heat is why it is so effective as a coolant and why coastal climates are mild.
Molar Heat Capacity
For gases and chemical processes it is often more natural to work in moles. The molar heat capacity (at constant volume) gives:
Where is the number of moles and has units of J/(mol·K).
Mayer's Relation for Ideal Gases
For an ideal gas, the molar heat capacity at constant pressure exceeds by exactly , the universal gas constant:
Where . This extra energy accounts for the work the gas does when it expands at constant pressure.
For a monatomic ideal gas: and .
Your Task
Implement the three functions below. Use as a module-level constant.