Heat capacity is the amount of heat energy required to raise the temperature of a substance by 1 degree Celsius (or 1 Kelvin).
Key Points:
- It measures how much heat a body can “store” before its temperature changes.
- Substances with high heat capacity (like water) can absorb a lot of heat without a big temperature rise.
- Substances with low heat capacity (like metals) heat up quickly with little energy.
- Heat capacity depends on the mass and type of substance.
Types:
- Specific Heat Capacity → Heat required to raise the temperature of 1 gram of a substance by 1 °C (or 1 K).
- Example: Water has a high specific heat, which is why it warms and cools slowly.
- Molar Heat Capacity → Heat required to raise the temperature of 1 mole of a substance by 1 °C (or 1 K).
Examples in Daily Life:
- Water in oceans absorbs large amounts of heat, helping regulate Earth’s climate.
- Cooking utensils made of metals heat up quickly because metals have low heat capacity.
- Car radiators use water because it can absorb more heat before its temperature rises.
In short: Heat capacity tells us how much heat energy is needed to change the temperature of a substance and explains why some materials heat up or cool down faster than others.