Ramendra C Mukerjee Solutions for Chapter: Chemical Equilibrium, Exercise 1: PROBLEMS

$\mathrm{HI}$ is introduced into three identical $500 \mathrm{mL}$ bulbs at $350°\mathrm{C}$. Each bulb is opened at different time intervals and analysed for ${\mathrm{I}}_2$ by titrating with $0.015 \mathrm{M}$ hypo solution.

$\left({\mathrm{I}}_2+2{\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3\to {\mathrm{Na}}_2{\mathrm{S}}_4{\mathrm{O}}_6+2\mathrm{NaI}\right)$

Calculate ${\mathrm{K}}_{\mathrm{c}}$ for $2\mathrm{HI}\rightleftharpoons {\mathrm{H}}_2+{\mathrm{I}}_2$ at $350°\mathrm{C}$. $( \mathrm{Give} \mathrm{answer} = {\mathrm{K}}_{\mathrm{c}} \times 100)$

$[$Hint: $\mathrm{Moles}$of ${\mathrm{I}}_2=\frac{1}{2}\left(\mathrm{moles}\right.$ $\left.{\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3\right)$ $=\frac{1}{2}\left(\mathrm{molarity} \times \text{ vol. }\right)$ in $\mathrm{L}$.$]$

A flask contains ${\mathrm{NH}}_4\mathrm{Cl} \left(\mathrm{s}\right)$ in equilibrium with its decomposition products. ${\mathrm{NH}}_4\mathrm{Cl} \left(\mathrm{s}\right)\rightleftharpoons {\mathrm{NH}}_3 \left(\mathrm{g}\right)+\mathrm{HCl} \left(\mathrm{g}\right)$ For this reaction, $\mathrm{\Delta H}=176\mathrm{kJ} {\mathrm{mole}}^{-1}$. How is the mass of ${\mathrm{NH}}_3$ in the flask affected by the following disturbances? 

$\mathrm{HCl}$is added

A flask contains ${\mathrm{NH}}_4\mathrm{Cl} \left(\mathrm{s}\right)$ in equilibrium with its decomposition products. ${\mathrm{NH}}_4\mathrm{Cl} \left(\mathrm{s}\right)\rightleftharpoons {\mathrm{NH}}_3 \left(\mathrm{g}\right)+\mathrm{HCl} \left(\mathrm{g}\right)$ For this reaction, $\mathrm{\Delta H}=176\mathrm{kJ} {\mathrm{mole}}^{-1}$. How is the mass of ${\mathrm{NH}}_3$ in the flask affected by each of the following disturbances? (${\mathrm{NH}}_4\mathrm{Cl}$ is added with no appreciable change in volume)

A flask contains ${\mathrm{NH}}_4\mathrm{Cl} \left(\mathrm{s}\right)$ in equilibrium with its decomposition products. ${\mathrm{NH}}_4\mathrm{Cl} \left(\mathrm{s}\right)\rightleftharpoons {\mathrm{NH}}_3 \left(\mathrm{g}\right)+\mathrm{HCl} \left(\mathrm{g}\right)$ For this reaction, $\mathrm{\Delta H}=176\mathrm{kJ} {\mathrm{mole}}^{-1}$. How is the mass of ${\mathrm{NH}}_3$ in the flask affected by the following disturbances?

 A large amount of ${\mathrm{NH}}_4\mathrm{Cl}$ is added decreasing the volume available to the gases.

Chlorine molecules are $1.0\%$ dissociated at $975 \mathrm{K}$ at a pressure of $1.0$ $\mathrm{atm}$$(1.0\%$ of the pressure is due to $\mathrm{Cl} \mathrm{atoms}$). In ${\mathrm{Cl}}_2 \left(\mathrm{g}\right)\rightleftharpoons \mathrm{Cl} \left(\mathrm{g}\right)+\mathrm{Cl} \left(\mathrm{g}\right)$, calculate ${\mathrm{K}}_{\mathrm{p}}$ and ${\mathrm{K}}_{\mathrm{c}}$.

Show that, $2.303 \log \mathrm{K}=-\frac{\mathrm{\Delta H}°}{\mathrm{RT}}+\frac{\mathrm{\Delta S}°}{\mathrm{R}}$.

Calculate the equilibrium ratio of $\mathrm{C}$ to $\mathrm{A}$ if $2.0$ $\mathrm{moles}$ each of $\mathrm{A}$ and $\mathrm{B}$ were allowed to come to equilibrium at $300 \mathrm{K}$.

$\mathrm{A}+\mathrm{B}\rightleftharpoons \mathrm{C}+\mathrm{D}; \mathrm{\Delta G}°=460 \mathrm{cal}$.

Calculate $\mathrm{\Delta E}°$  (in kJ) for the reaction $2\mathrm{A} \left(\mathrm{g}\right)+\mathrm{B} \left(\mathrm{g}\right)\rightleftharpoons {\mathrm{A}}_2\mathrm{B} \left(\mathrm{g}\right)$ for which $\mathrm{\Delta S}°=5.0$ $\mathrm{J}/\mathrm{K},$ $\mathrm{K}=1.0\times {10}^{10}$ and $\mathrm{T}=300 \mathrm{K}$.