Heat Capacity Calculator
Calculate heat energy needed to raise or lower a substance's temperature using Q=mcΔT.
Enter mass, specific heat capacity, and temperature change in C or F.
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