joule per kilogram kelvin

SI coherent derived unit whose name and symbol includes an SI coherent derived unit with a special name and symbol

Name	Symbol	Quantity	Base units
joule per kilogram kelvin	J/(kg K)	specific heat capacity, specific entropy	m2 s−2 K−1
The joule per kilogram kelvin, symbol J/(kg K) or J kg-1 K−1, is the SI coherent derived unit of specific heat capacity, and specific entropy.   One joule per kilogram kelvin is equal to the specific heat capacity of a substance that requires one joule of heat energy to raise the temperature of one kilogram of the substance by one kelvin.
Definition			h−1 c2 ΔνCs−1 k

Specific heat capacity

The amount of heat energy needed to raise the temperature of an object by one kelvin depends on the object’s substance. The amount of energy needed is also directly proportional to the mass of the object.

To be able to make meaningful comparisons of the heat capacity of different substances, it is useful to measure the heat energy needed to raise the temperature of a unit mass of each substance. In the SI, the unit of mass is the kilogram.

The amount of heat energy needed to raise the temperature of one kilogram of a substance by one kelvin is equal to the specific heat capacity of the substance.

Examples of specific heat capacity

Substance	Specific heat capacity at 298 K (25 °C) / J kg-1 K−1
Liquids
Water	4181
Methanol	2140
Ethanol	2440
Mercury	139
Solids
Water (ice) at -10 °C	2050
Aluminium	897
Graphite	790
Tin	227
Gases
Water (steam) at 100 °C	2080
Helium	5193
Nitrogen	1040
Oxygen	918