Heat Capacity Definition

What Is Heat Capacity in Chemistry?

Water is a chemical with an extremely high heat capacity. It takes a lot of energy to raise its temperature.
Water is a chemical with an extremely high heat capacity. It takes a lot of energy to raise its temperature. Erika Straesser / EyeEm / Getty Images

Heat Capacity Definition

Heat capacity is the amount of heat energy required to raise the temperature of a body a specified amount. In SI units, heat capacity (symbol: C) is the amount of heat in joules required to raise the temperature 1 Kelvin.

Heat capacity of a material is affected by the presence of hydrogen bonds. The intermolecular forces make it more difficult to increase the kinetic energy and thus temperature of a material. This is why water, ammonia, and ethanol have high heat capacity values. Impurities in a sample also have a dramatic effect on heat capacity. Heat properties of an alloy can vary dramatically from that of its component elements. Trace amounts of contaminants in a sample can change its heat capacity versus that of a pure sample.

Examples: One gram of water has a heat capacity of 4.18 J. One gram of copper has a heat capacity of 0.39 J.

Sources

  • Emmerich Wilhelm & Trevor M. Letcher, Eds. (2010). Heat Capacities: Liquids, Solutions and Vapours, Cambridge, U.K.:Royal Society of Chemistry, ISBN 0-85404-176-1.
  • Halliday, David; Resnick, Robert (2013). Fundamentals of Physics. Wiley. p. 524.
  • Kittel, Charles (2005). Introduction to Solid State Physics (8th ed.). Hoboken, New Jersey, USA: John Wiley & Sons. p. 141. ISBN 0-471-41526-X.