Calorimetry Calculator — q = m·c·ΔT & Mixture Temperature

Frequently asked questions

What is the basic calorimetry formula?

The basic formula is q = m · c · ΔT, where q = heat energy (joules), m = mass (grams), c = specific heat (J/(g·°C)), and ΔT = temperature change in °C. Example: heating 250 grams of water from 20 °C to 80 °C requires q = 250 × 4.184 × 60 = 62,760 J (62.76 kJ, equivalent to 15 kcal).

What is the specific heat of water?

The specific heat of liquid water is 4.184 J/(g·°C) — the highest among common substances, which is why water heats and cools slowly. Other presets in this calculator: aluminium 0.897; iron 0.449; copper 0.385; and ice 2.09 J/(g·°C).

How do you calculate the mixture temperature of two bodies?

Use the principle of heat exchange: heat released by the hot body equals heat absorbed by the cold body, so Tf = (m₁·c₁·T₁ + m₂·c₂·T₂) / (m₁·c₁ + m₂·c₂). Example: 100 grams of aluminium at 90 °C mixed with 200 grams of water at 20 °C gives Tf = 24,809 / 926.5 ≈ 26.78 °C.

Can this calculator handle melting ice or boiling water?

No. This calculator only models temperature change without phase change (q = m · c · ΔT). Melting ice or boiling water requires latent heat (heat of fusion and heat of vaporization), which is not computed here, so results are invalid if the temperature crosses the melting or boiling point.

Which units does this calculator support?

Energy: joules (J), kilojoules (kJ), calories (cal), and kilocalories (kcal). Mass: grams, kilograms, and pounds (lb). Specific heat: J/(g·°C), J/(kg·°C), and cal/(g·°C). Temperature: °C, °F, and K; for ΔT you can also use a difference in °F.

How long does it take to heat water?

Use the Power & Time mode with t = q / P. Example: heating 250 grams of water from 20 °C to 80 °C needs 62,760 J; with a 1,500 W heater, the theoretical time is 62,760 / 1,500 = 41.84 seconds — not counting heat lost to the surroundings.