Chapter 2, Problem 2.28NP

Interpretation Introduction

Interpretation: The value of q, w, $\Delta H$$\Delta U$ for the process containing 3.50 mol of an ideal gas with $C_{V,m}=3R/2$ needs to be determined if the gas expanded adiabatically against external pressure 1.45 bar. The initial temperature, initial pressure and final pressure is 310 K, 15.2 bar and 1.45 bar respectively.

Concept Introduction: The change in internal energy is calculated as follows:

  $\Delta U=n{C}_{V.m}\left(T_f-T_i\right)$

Here, n is number of moles, $C_{V,m}$ is molar heat at constant volume and T is temperature.

The work done is represented as follows:

  $w=-P_{\text{external}}\Delta V$

Here, P is external pressure and $\Delta V$ is change in volume.

The enthalpy of a reaction is represented as follows:

  $\Delta H=\Delta U+nR\Delta T$

Here, n is number of moles, R is Universal gas constant and $\Delta T$ is change in temperature.