(Or specific heat.) The heat capacity of a system divided by its mass. It is a property solely of the substance of which the system is composed. As with heat capacities, specific heats are commonly defined for processes occurring at either constant volume () or constant pressure (). For an ideal gas, both are constant with temperature and related by = + with the gas constant. For dry air at 273 K, For moist air, the specific heat capacities of the dry air and water vapor must be combined in proportion to their respective mass fractions. Dutton, J. A., 1995: Dynamics of Atmospheric Motion, Dover Press, 41â€“45, 406â€“410. Sommerfeld, A., 1964: Thermodynamics and Statistical Mechanics, Academic Press, p. 45.
Specific heat capacity, also known simply as specific heat (Symbol: C or c) is the measure of the heat energy required to raise the temperature of a given amount of a substance by one degree. Commonly, the amount is specified by mass; for example, water has a mass-specific heat capacity of about 4184 joules per kelvin per kilogram. Volume-specific and molar-specific heat capacities are also used.