Question

Find the internal pressure p_i of a liquid if its density ρ and specific latent heat of vaporization q are known. The heat q is assumed to be equal to the work performed against the forces of the internal pressure, and the liquid obeys the Van der Waals equation. Calculate p_i in water.

Answer 1

The internal pressure being  a/V^2'the work done in condensation is

This by assumption is Mq , M being the molecular weight and V_l , V_g being the molar volumes of the liquid and gas.

where ρ is the density of the liquid. For water p_i = 3.3 x 10¹³ atm