Chapter 7, Problem 7.18P

Interpretation Introduction

(a)

Interpretation:

The validation of expression $Q=\Delta H$, taking the steam as the system is to be stated. The validation of the fact that the final steam temperature is $\text{480 K}$ is to be stated. The final cylinder volume, expansion work done by the steam and $\Delta U\left(\text{J}\right)$ are to be determined.

Concept introduction:

The equation of energy for closed-system is given by the formula,

$Q-W=\Delta U+\Delta E_{\text{k}}+\Delta E_{\text{p}}$

Here,

• $W$ is the work done by the system.
• $Q$ is the heat absorbed by the system.
• $\Delta U$ is the change in internal energy.
• $\Delta E_{\text{k}}$ is the change in kinetic energy.
• $\Delta E_{\text{p}}$ is the change in potential energy.

Interpretation Introduction

(b)

Interpretation:

The conditions which would have been only an approximation if the cylinder were not horizontal are to be predicted.

Concept introduction:

The equation of energy for closed-system is given by the formula,

$Q-W=\Delta U+\Delta E_{\text{k}}+\Delta E_{\text{p}}$

Here,

• $W$ is the work done by the system.
• $Q$ is the heat absorbed by the system.
• $\Delta U$ is the change in internal energy.
• $\Delta E_{\text{k}}$ is the change in kinetic energy.
• $\Delta E_{\text{p}}$ is the change in potential energy.