Heat Capacity Calculator
Calculate the heat energy needed to raise or lower the temperature of any substance using specific heat capacity values.
Heat capacity describes how much energy is required to raise the temperature of a substance by a given amount. It is a fundamental concept in thermodynamics and has practical applications in cooking, engineering, climate science, and industrial processes.
The Specific Heat Capacity Formula
Q = m × c × ΔT
Where:
- Q = heat energy transferred (joules, J)
- m = mass of the substance (kg or grams depending on units)
- c = specific heat capacity (J/g·°C or J/kg·K)
- ΔT = change in temperature (°C or K — the change is the same in both)
Example: Heating Water
To raise 1 kg of water from 20°C to 100°C:
- m = 1 kg = 1,000 g
- c = 4.186 J/g·°C (water)
- ΔT = 100 − 20 = 80°C
- Q = 1,000 × 4.186 × 80 = 334,880 J = 334.9 kJ
Specific Heat Capacities of Common Materials
| Material | Specific Heat (J/g·°C) |
|---|---|
| Water (liquid) | 4.186 |
| Ice | 2.090 |
| Steam | 2.010 |
| Ethanol | 2.440 |
| Aluminium | 0.900 |
| Iron / Steel | 0.450 |
| Copper | 0.385 |
| Glass | 0.840 |
| Concrete | 0.880 |
| Air (at 1 atm) | 1.005 |
| Sand / soil | 0.840 |
| Wood (dry) | 1.700 |
Why Water’s High Heat Capacity Matters
Water has an exceptionally high specific heat capacity (4.186 J/g·°C) compared to most other substances. This is why:
- Oceans moderate coastal climates — water absorbs and releases heat slowly
- Sweating cools the body efficiently — water evaporation removes large amounts of heat
- Cooking water takes more energy than heating the same mass of most other foods
Calories and Joules
1 calorie (cal) = 4.184 J (the heat needed to raise 1 g of water by 1°C) 1 food Calorie (kcal) = 4,184 J = 1,000 cal