Specific heat calculator
How much energy it takes to heat a body: Q = c·m·ΔT.
Fill in the fields and the result will appear here automatically.
Calculate heat received or released as a body changes temperature without changing phase. Here Q=c·m·ΔT with c>0 and m>0; negative Q and ΔT describe cooling. In the inverse mass mode, Q and ΔT must have the same sign. This is heat in joules, not appliance power or electricity drawn from the supply.
How it works
Formula and logic
The heat equals specific heat capacity times mass times temperature change: Q = c·m·ΔT. A change in kelvin and in degrees Celsius is numerically the same.
Example
For 2 kg of water with c=4186 J/(kg·K) and ΔT=50 K, the result is 418,600 J or 0.1163 kWh. Cooling by 50 K reverses the sign of Q but keeps its magnitude in this model.
Fields and units
- What to find — list option
- Mass — kg
- Specific heat capacity — J/(kg·K)
- Temperature change — K
- Energy — J
How to use
- — Choose what you are after: the energy, the temperature change or the mass.
- — Enter the two visible known quantities and c. The example c=4186 J/(kg·K) is for water; choose c for the material, temperature and process. Q=ΔT=0 cannot determine mass.
- — For cooling give a negative change: the energy comes out with a minus sign.
Method and limitations
- Calculation method
- Formula and logic
- Data or methodology source
- OpenStax: heat capacity without phase change
- Limitation
- Constant entered heat capacity within one phase and specified conditions. Phase changes, heating the container, heat losses and source efficiency are not included.
FAQ
How is this different from conduction through a layer?
That gives the heat flow through a construction in watts, driven by conductivity and thickness. This gives the heat needed to warm a substance in joules, driven by mass and heat capacity.
Is melting or boiling included?
No. Melting or boiling needs separate latent heat at the relevant pressure and temperature. A process containing both a temperature change and a phase change must be split into stages.
Kelvin or Celsius?
For a CHANGE in temperature it makes no difference: the scales differ only in where they start, and the size of a degree is identical.
Why can the energy be negative?
Because the body is cooling and giving up heat rather than absorbing it. The sign shows direction, not an error.