Glossary
specific heat
Specific heat is the energy needed to raise one gram of a substance by one degree Celsius, in J/(g·°C); water's 4.18 is high, so it resists a temperature change.
Specific heat is the energy it takes to raise one gram of a substance by one degree Celsius, written in joules per gram per degree, J/(g·°C). Water's is 4.18 J/(g·°C), and few common substances come near it: aluminum is about 0.900 J/(g·°C), so the same energy lifts a gram of aluminum nearly five times as far as it lifts a gram of water. The arithmetic is one formula, q = m × c × ΔT — energy in joules, mass in grams, specific heat, and the temperature change. Heating 100 g of water by 10 °C takes 100 × 4.18 × 10 = 4,180 J; the same mass of aluminum needs about 900 J for the same 10 °C. That high value is why a pot of water takes so long to come to a boil, why the sea smooths a coast's climate, and why the body, which is mostly water, holds its temperature through a hot afternoon and a cold night.
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Related terms
- matter — Matter is anything with mass that takes up space, and it exists as a solid, a liquid, a gas or a plasma.
Source: NIST periodic table and reference data for the atomic masses and half-life figures, NIH PubChem for the substance data, and NIST Special Publication 811 for the unit conventions — the same sources the chemistry guide cites. All three are US federal government material, not subject to copyright in the United States. Every definition, example and calculation above was written for this course; no dictionary or textbook text is reproduced. (NIST and PubChem accessed 2026-10-26; definitions written 2026-10-27)