🔥 Specific Heat Calculator (q = mcΔT)
Enter any three of heat, mass, specific heat and temperature change, and q = mcΔT gives the fourth.
Heat energy
10460 J
q = mcΔT, with c in J/(g·°C), use grams and °C, giving q in joules. 🔒 Computed in your browser.
How the specific heat calculator (q = mcδt) works
The heat absorbed or released is q = m·c·ΔT, where m is mass, c is specific heat capacity, and ΔT is the temperature change. Enter any three quantities and the tool solves for the fourth. Water’s specific heat is 4.184 J/(g·°C). Rearranged: m = q/(cΔT), c = q/(mΔT) and ΔT = q/(mc). For example, heating 200 g of water by 25 °C needs q = 200 × 4.184 × 25 = 20,920 J, about 20.9 kJ.
Keep units consistent: with c in J/(g·°C), use grams and °C, and q comes out in joules. A positive q means heat absorbed; negative means released.
Frequently asked questions
What is the specific heat formula?
q = mcΔT: heat (q) equals mass (m) times specific heat capacity (c) times the temperature change (ΔT = T_final − T_initial).
What is the specific heat of water?
About 4.184 J/(g·°C), the energy to raise 1 gram of water by 1 °C. This tool pre-fills it and lets you change it for other substances.
How do I solve for each variable?
Rearrange q = mcΔT: m = q/(cΔT), c = q/(mΔT), ΔT = q/(mc). Enter the three known values and the tool computes the fourth.
What does a negative q mean?
The substance released heat (cooled down): if ΔT is negative, q is negative. A positive q means it absorbed heat and warmed up.
What units should I use?
With c in J/(g·°C), use mass in grams and ΔT in °C, giving q in joules. Keep the units consistent throughout.
How much energy heats a cup of water?
For 250 g of water raised from 20 °C to 100 °C (ΔT = 80 °C): q = 250 × 4.184 × 80 = 83,680 J ≈ 83.7 kJ. Enter the mass, 4.184 for c, and 80 for ΔT.
Why does water need so much energy to heat?
Water has an unusually high specific heat (4.184 J/g·°C) because of extensive hydrogen bonding. Metals are far lower, copper is about 0.385, so the same energy warms copper roughly ten times as much per gram.
What is the difference between specific heat and heat capacity?
Specific heat (c) is per gram, the energy to raise 1 g by 1 °C. Heat capacity is for the whole object: C = m·c. A large pot has a big heat capacity even though its metal’s specific heat is small.
Does q = mcΔT cover melting or boiling?
No. It only applies while a substance stays in one phase and its temperature changes. During a phase change the temperature holds steady, and you use the latent heat (q = m·L) instead.