Specific Heat Calculator (Q = mcΔT)
Calculate heat energy Q = mcΔT. Enter mass (kg), specific heat capacity (J/kg·K) and temperature change (ΔT in °C or K) to get heat in Joules.
How to use this tool
- Enter mass, specific heat capacity and temperature change δt in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your heat energy q and the full breakdown beneath it.
The heat equation Q = mcΔT gives the energy transferred when a substance of mass m and specific heat capacity c changes temperature by ΔT. Positive Q means energy absorbed (heating); negative means released (cooling).
Formula
Q = m × c × ΔT
Where: Q = heat energy (J), m = mass (kg), c = specific heat capacity (J/kg·K), ΔT = temperature change (°C or K).
How it works
This calculator applies the calorimetry equation Q = mcΔT to find the heat energy transferred when a substance of known mass changes temperature. A positive ΔT means the substance absorbs heat (heating); a negative ΔT means it releases heat (cooling).
The result is rounded to 3 decimal places. The formula assumes a constant specific heat capacity over the temperature range, which is a good approximation for moderate temperature intervals but may differ slightly for very large ranges where c varies.
Worked example
Worked example
- Given: mass m = 1 kg, specific heat of water c = 4186 J/kg·K, temperature change ΔT = 10 °C.
- Apply the formula: Q = m × c × ΔT = 1 × 4186 × 10.
- Q = 41 860 J.
Heat energy Q = 41860 J (absorbed, heating).
Key terms
- Specific heat capacity (c)
- The amount of energy required to raise 1 kg of a substance by 1 K. Water's value is approximately 4186 J/kg·K.
- Heat energy (Q)
- The thermal energy transferred into or out of a substance, measured in Joules.
- Temperature change (ΔT)
- The difference between final and initial temperature. A positive value indicates heating; a negative value indicates cooling.
- Calorimetry
- The science of measuring heat transfer during physical or chemical processes.
- Joule (J)
- The SI unit of energy. 1 J = 1 kg·m²/s².
Frequently asked questions
- What are common specific heat values?
- Water: 4186 J/kg·K (very high — why it's used as a coolant), iron: 450, aluminium: 900, copper: 385, ethanol: 2440 J/kg·K.
- Is ΔT in Celsius or Kelvin?
- Either, since a change of 1 °C equals a change of 1 K. Always use the magnitude of the change.