# Clausius–Clapeyron relation

## Description

The Clausius–Clapeyron relation, named after Rudolf Clausius and Benoît Paul Émile Clapeyron, is a way of characterizing a discontinuous phase transition between two phases of matter of a single constituent. On a pressure–temperature (P–T) diagram, the line separating the two phases is known as the coexistence curve. The Clausius–Clapeyron relation gives the slope of the tangents to this curve.

Related formulas## Variables

dP | slope of the tangent to the coexistence curve at any point, (N/m^{2}) |

dT | temperature difference (K) |

L | latent heat (joule/kg) |

T | temperature (K) |

Δ_{v} | specific volume change of the phase transition (m^{3}/kg) |