Chapter 12.2, Problem 12.1AFP

Interpretation Introduction

Interpretation:

The heat released or absorbed when $2.25\text{ mol}$ of ${\text{H}}_{\text{2}}\text{O}$ undergoes the change represented in the scene is to be calculated.

Concept introduction:

Molar heat capacity $\left(C_{\text{m}}\right)$ of a substance is the amount of heat needed to raise the temperature of $1\text{mol}$ of a substance by $1\text{K}$. The formula to calculate heat required is as follows:

$q=\left(\text{mol}\right)\left(C_{\text{m}}\right)\left(T_2-T_1\right)$ (1)

Here,

$T_2$ is the final temperature.

$T_1$ is the initial temperature.

$q$ is the heat released or absorbed.

$C_{\text{m}}$ is the molar heat capacity of the substance.

The formula to calculate heat at phase change is as follows:

$q=\left(\text{mol}\right)\left(\Delta H\right)$ (2)

Here,

$\Delta H$ is the enthalpy change.