Specific Heat Calculator
Heat Energy Q (J)41,860.0000
Mass m (kg)1.0000
Specific Heat c (J/kg·K)4,186.0000
Temperature Change ΔT (K)10.0000
The Specific Heat Calculator solves the calorimetry equation Q = m·c·ΔT, which links the heat energy absorbed or released by a substance to its mass, its specific heat capacity, and the resulting temperature change. Pick any one of the four quantities to solve for, enter the other three, and the tool rearranges the formula. A negative temperature change yields a negative Q, signalling that heat is being released rather than absorbed.
Formula
Q = m × c × ΔT
- Q
- Heat energy transferred (joules); negative means heat released
- m
- Mass of the substance (kilograms)
- c
- Specific heat capacity (J per kg per kelvin)
- ΔT
- Change in temperature, final minus initial (kelvin)
How it works
- Select the variable to solve for: heat Q, mass m, specific heat c, or temperature change ΔT.
- Enter the three known values; specific heat is in J/(kg·K), mass in kilograms, and ΔT in kelvin (equal to degrees Celsius for a difference).
- The calculator evaluates Q = m·c·ΔT or its rearrangement, returning heat in joules and preserving the sign of ΔT.
Worked example
Heating 1 kg of water by 10 °C (specific heat 4186 J/kg·K).
- Q = m × c × ΔT = 1 × 4186 × 10.
- Q = 41,860 J.
- That is about 41.86 kJ, or roughly 10 kilocalories.
Heat required = 41,860 J (≈ 41.86 kJ).
Frequently asked questions
- What is specific heat capacity?
- Specific heat capacity (c) is the energy needed to raise one kilogram of a substance by one kelvin. Water is unusually high at about 4186 J/(kg·K), while metals like copper are far lower, near 385 J/(kg·K).
- Why can the heat value be negative?
- A negative temperature change (cooling) produces a negative Q, which means the substance is releasing heat to its surroundings rather than absorbing it. The magnitude is the amount of energy given off.
- Do I use Celsius or Kelvin for ΔT?
- Either works because the equation uses a temperature difference, and a change of 1 °C equals a change of 1 K. Only an absolute temperature would force you to use kelvin.
- Does this account for phase changes like boiling?
- No. Q = m·c·ΔT only covers heating or cooling within a single phase. Melting or boiling requires latent heat (Q = m·L), which adds energy at constant temperature and is not part of this formula.