Chapter 2, Problem 2.43NP

Interpretation Introduction

Interpretation: The value of q, w, $\Delta U$ and $\Delta H$ for a1.75 mol of an ideal gas needs to be determined if the gas undergoes isothermally compressed from initial and final volume 62.0 L and 19.0 L respectively. The external pressure is 2.80 atm.

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.