Subsection 10.3.2 Latent Heat
Heat absorbed or released by the material during phase change is called latent heat. There is no temperature change during a phase change hence this energy is hidden from temperature scale. The energy dissipated or released during phase change is in adjustment of particles potential energy in the bonds. Hence the amount of heat \(Q\) during phase change is proportional to the mass of a material. That is,
\begin{equation*}
Q\propto m
\end{equation*}
\begin{equation*}
\therefore\quad Q = m L
\end{equation*}
where \(L\) is a latent heat during phase change. It is also a material property. The latent (hidden) heat of fusion for water at \(0^{o}C\) is approximately \(334 \,joules/g\) (79.7 calories/g), and the latent heat of vaporization at \(100^{o}C\) is about 2,230 joules per gram (or, 533 calories per gram) .
