Chapter 6, Problem 6.56P

Interpretation Introduction

Interpretation:

The values of $\Delta H\text{ and }\Delta S$ for the change in state of ${\text{H}}_2\text{S}$ gas is to be calculated.

Concept Introduction:

The formula to calculate enthalpy change of vapor $\left(\Delta H\right)$ from temperature $T_1\left(\text{K}\right)\text{ to }{T}_2\left(\text{K}\right)$ is:

  $\Delta H={\displaystyle {\int }_{T_1}^{T_2}{C}_p^{ig}dT}+H_2^R-H_1^R$   ......(1)

Value of $C_p^{ig}$ is taken from table C.1. $H_i^R$ at state $i$ is defined as:

  $H_i^R={\left(H_i^R\right)}^0+\omega {\left(H_i^R\right)}^1$   ......(2)

Here, ${\left(H_i^R\right)}^0\text{ and }{\left(H_i^R\right)}^1$ are given in table D.5 and D.6.

The formula to calculate entropy change of vapor $\left(\Delta S\right)$ from temperature $T_1\left(\text{K}\right)\text{ to }{T}_2\left(\text{K}\right)$ is:

  $\Delta S={\displaystyle {\int }_{T_1}^{T_2}{C}_p^{ig}\frac{dT}{T}}-R\ln \frac{P_2}{P_1}+S_2^R-S_1^R$   ......(3)

Value of $C_p^{ig}$ is taken from table C.1. $S_i^R$ at state $i$ is defined as:

  $S_i^R={\left(S_i^R\right)}^0+\omega {\left(S_i^R\right)}^1$   ......(4)

Here, ${\left(S_i^R\right)}^0\text{ and }{\left(S_i^R\right)}^1$ are given in table D.9 and D.10.