Clasius-Clapeyron equation for water vapor

Input(s)

$L_{v}$: Heat of Vaporization of one mole of Liquid $(\mathrm{J} / \mathrm{mol})$

$\mathrm{T}_{1}$: Absolute Temperature of Condition $1\left({ }^{\circ} \mathrm{F}\right)$

$\mathrm{T}_{2}$: Absolute Temperature of Condition $2\left({ }^{\circ} \mathrm{F}\right)$

$R$: Gas Constant for Water Vapor $\left(\mathrm{psi} / \mathrm{mol}^{\circ} \mathrm{F} \mathrm{s}{ }^{2}\right)$

Output(s)

$p_{v 1}$: Vapor Pressure at the Temperature $\mathrm{T}_{1}(\mathrm{psi})$

$p_{v 2}$: Vapor Pressure at the Temperature $\mathrm{T}_{2}(\mathrm{psi})$

Formula(s)

$$ \ln \left(\frac{\mathrm{p}_{\mathrm{v} 1}}{\mathrm{p}_{\mathrm{v} 2}}\right)=\frac{\mathrm{L}_{\mathrm{v}}}{\mathrm{R}}\left(\frac{1}{\mathrm{~T}_{1}}-\frac{1}{\mathrm{~T}_{2}}\right) $$

Reference(s)

McCain Jr, W. D. (1990). Properties of Petroleum Fluids. PennWell Corporation. Page: 54.