Embibe Experts Solutions for Chapter: Thermodynamics, Exercise 4: Exercise 4

Enthalpy of combustion of methane and ethane are $-210 \mathrm{k} \mathrm{cal}/\mathrm{mol}$ and $-368 \mathrm{k} \mathrm{cal}/\mathrm{mol}$ respectively. The enthalpy of combustion of decane is

What is the entropy change (in ${\mathrm{JK}}^{–1} {\mathrm{mol}}^{–1}$), when one mole of ice is converted into water at $0 °\mathrm{C}$? (The enthalpy change for the conversion of ice to liquid water is $6.0 \mathrm{kJ} {\mathrm{mol}}^{–1}$ at $0 °\mathrm{C}$).
 

The enthalpy of combustion of ${\mathrm{H}}_2,$ cyclohexene $\left({\mathrm{C}}_6{\mathrm{H}}_{10}\right)$ and cyclohexane $\left({\mathrm{C}}_6{\mathrm{H}}_{12}\right)$ are $-241, -3800$ and $-3920 \mathrm{kJ}/\mathrm{mol}$ respectively. Heat of hydrogenation of cyclohexene is:

If the enthalpy change for the transition of liquid water to steam is $30 \mathrm{kJ} {\mathrm{mol}}^{-1}$ at $27° \mathrm{C}$, the entropy change for the process would be

The correct thermodynamic conditions for the spontaneous reaction at all temperatures is

For a given reaction, $\mathrm{\Delta H}=35.5 \mathrm{kJ} {\mathrm{mol}}^{-1}$ and $\mathrm{\Delta S}=83.6{\mathrm{JK}}^{-1} {\mathrm{mol}}^{-1}$.The reaction is spontaneous at :(Assume that $\mathrm{\Delta H}$ and $\mathrm{\Delta S}$ do not vary with temperature)

In conversion of lime-stone to lime, ${\mathrm{CaCO}}_{3\left(\mathrm{s}\right)}⟶{\mathrm{CaO}}_{\left(\mathrm{s}\right)}+{\mathrm{CO}}_{2\left(\mathrm{g}\right)}$ the values $△\mathrm{H}°$ and $△\mathrm{S}°$ are $179.1 \mathrm{kJ} {\mathrm{mol}}^{-1}$ and $160.2 \mathrm{J} {\mathrm{K}}^{-1}-{\mathrm{mol}}^{-1}$ respectively at $298 \mathrm{K}$ and $1 \mathrm{bar}$. Assuming that $△\mathrm{H}°$ and $△\mathrm{S}°$ do not change with temperature, temperature above which conversion of lime stone to lime will be spontaneous is :

For complete combustion of ethanol, ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\left(\mathrm{l}\right)+3{\mathrm{O}}_2\left(\mathrm{g}\right)⟶2{\mathrm{CO}}_2\left(\mathrm{g}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$, the amount of heat produced as measured in bomb calorimeter, is $1364.47 \mathrm{kJ} {\mathrm{mol}}^{-1}$ at $25°\mathrm{C}$. Assuming ideality the enthalpy of combustion, ${\mathrm{\Delta }}_{\mathrm{C}}\mathrm{H}$ reaction will be :

$\left(\mathrm{R}=8.314 \mathrm{kJ} {\mathrm{mol}}^{-1}\right)$