Embibe Experts Solutions for Chapter: Thermodynamics, Exercise 1: Level 1

The standard heat of combustion of solid boron is equal to:

The entropy change in the isothermal reversible expansion of $2$ $\mathrm{moles}$ of an ideal gas from $10$ to $100 \mathrm{L}$ at $300 \mathrm{K}$ is: 

For the isothermal reversible expansion of an ideal gas:

The latent heat of melting of ice at $0°\mathrm{C}$ is $6 \mathrm{kJ} {\mathrm{mol}}^{-1}$. The entropy change during the melting in ${\mathrm{JK}}^{-1}$ is closest to 

Given:

$\mathrm{NO} \left(\mathrm{g}\right)+{\mathrm{O}}_{3 }\left(\mathrm{g}\right)⟶{\mathrm{NO}}_2 \left(\mathrm{g}\right)+{\mathrm{O}}_2 \left(\mathrm{g}\right) \mathrm{\Delta H}=-198.9 \mathrm{kJ}/\mathrm{mol}$

${\mathrm{O}}_{3 }\left(\mathrm{g}\right)⟶3/2{\mathrm{O}}_{2 }\left(\mathrm{g}\right) \mathrm{\Delta H}=-142.3 \mathrm{kJ}/\mathrm{mol}$

${\mathrm{O}}_2 \left(\mathrm{g}\right)⟶2\mathrm{O} \left(\mathrm{g}\right) \mathrm{\Delta H}=+495.0 \mathrm{kJ}/\mathrm{mol}$

The enthalpy change $\left(∆\mathrm{H}\right)$ for the following reaction is:

$\mathrm{NO} \left(\mathrm{g}\right)+\mathrm{O} \left(\mathrm{g}\right)⟶{\mathrm{NO}}_2 \left(\mathrm{g}\right)$

For the following reaction, $\mathrm{C}\left(\mathrm{diamond}\right)+{\mathrm{O}}_2⟶{\mathrm{CO}}_2\left(\mathrm{g}\right); \mathrm{\Delta H}=-94.3 \mathrm{kcal}$

$\mathrm{C}\left(\mathrm{graphite}\right)+{\mathrm{O}}_2⟶{\mathrm{CO}}_2\left(\mathrm{g}\right); \mathrm{\Delta H}=-97.6 \mathrm{kcal}$.

The heat required to change $1 \mathrm{g}$ of $\mathrm{C}\left(\mathrm{diamond}\right)\to \mathrm{C}\left(\mathrm{graphite}\right)$ is:

$\mathrm{C}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)⟶{\mathrm{CO}}_2, \left(\mathrm{g}\right); {\mathrm{\Delta H}}_1=-94.3 \mathrm{kcal}/\mathrm{mol}$

$\mathrm{CO}\left(\mathrm{g}\right)+\frac{1}{2}{\mathrm{O}}_2\left(\mathrm{g}\right)⟶{\mathrm{CO}}_2\left(\mathrm{g}\right); {\mathrm{\Delta H}}_2=-67.4 \mathrm{kcal}/\mathrm{mol}$

${\mathrm{O}}_2\left(\mathrm{g}\right)⟶2\mathrm{O}\left(\mathrm{g}\right); {\mathrm{\Delta H}}_3=117.4 \mathrm{kcal}/\mathrm{mol}$

$\mathrm{CO}\left(\mathrm{g}\right)\to \mathrm{C}\left(\mathrm{g}\right)+\mathrm{O}\left(\mathrm{g}\right); ∆{\mathrm{H}}_4=230.6 \mathrm{kcal}/\mathrm{mol}$

Calculate $\mathrm{\Delta H}$ for $\mathrm{C}\left(\mathrm{s}\right)⟶\mathrm{C}\left(\mathrm{g}\right)$ in $\mathrm{kcal}/\mathrm{mol}$.

The ratio of the heat capacities ${\mathrm{C}}_{\mathrm{p}}/{\mathrm{C}}_{\mathrm{v}}$ for one mole of a gas is $1.67$. The gas is: