Chapter 6, Problem 6.7P

Interpretation Introduction

Interpretation:

Calculate the change in enthalpy and entropy $\Delta H$ and $\Delta S$ for the liquid ammonia at $270\text{K}$ if it is compressed from saturation pressure of $381\text{kPa}$ to $\text{1200 kPa}$ given that $V^l=1.551\times {10}^{-3}{\text{m}}^{\text{3}}{\text{.kg}}^{\text{-1}}$ and $\beta =2.095\times {10}^{-3}{\text{K}}^{\text{-1}}$ .

Concept Introduction:

For liquids, the following correlations for change in enthalpy and entropy $\Delta H$ and $\Delta S$ are applicable:

  ${\left(\frac{\partial S}{\partial P}\right)}_T=-\beta V$............(1)

And

  ${\left(\frac{\partial H}{\partial P}\right)}_T=(1-\beta T)V$............(2)