Chapter 7

At certain temperature compound \(\mathrm{AB}_{2}(\mathrm{~g})\) dissociates according to the reaction \(2 \mathrm{AB}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{AB}(\mathrm{g})+\mathrm{B}_{2}(\mathrm{~g})\) The value of \(K_{p}\) in terms of degree of dissociation ' \(\alpha\) ' and total pressure 'P' is (a) \(\mathrm{P} \frac{\alpha^{3}}{2}\) (b) \(\mathrm{P} \frac{\alpha^{2}}{3}\) (c) \(\mathrm{P} \frac{\alpha^{3}}{3}\) (d) \(\mathrm{P} \frac{\alpha^{2}}{2}\)

When \(\mathrm{NaNO}_{3}(\mathrm{~d}=2.0 \mathrm{~g} / \mathrm{cc})\) is heated in a closed vessel of \(100 \mathrm{ml}\), oxygen is liberated and \(\mathrm{NaNO}_{2}\) \((\mathrm{d}=1.5 \mathrm{~g} / \mathrm{cc})\) is left behind as per the reaction \(2 \mathrm{NaNO}_{3}(\mathrm{~s}) \rightleftharpoons 2 \mathrm{NaNO}_{2}(\mathrm{~s})+\mathrm{O}_{2}(\mathrm{~g}) .\) At equilibrium, the volumes of \(\mathrm{NaNO}_{3}\) left and \(\mathrm{NaNO}_{3}\) left and \(\mathrm{NaNO}_{2}\) produced are very small and can be neglected. Which of the following is a correct statement about this equilibrium? (a) Addition of \(30 \mathrm{~g}\) of \(\mathrm{NaNO}_{3}\) favours reverse reaction. (b) Addition of \(30 \mathrm{~g}\) of \(\mathrm{NaNO}_{2}\) favours forward reaction. (c) Increasing temperature favours reverse reaction. (d) None of these.

An element \(X\) being with oxygen and CO present in air as \(\mathrm{X}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons \mathrm{XO}_{2}(\mathrm{~g}) ; \mathrm{K}_{\mathrm{P}_{1}}=27\) \(\mathrm{X}(\mathrm{g})+\mathrm{CO}(\mathrm{g}) \rightleftharpoons \mathrm{XCO}(\mathrm{g}) ; \quad \mathrm{K}_{\mathrm{p}_{2}}=10^{4}\) When \(\mathrm{X}\) at \(1 \mathrm{~atm}\) is treated with air, \(25 \%\) of it is bound to \(\mathrm{CO}(\mathrm{g})\). The partial pressure of \(\mathrm{CO}(\mathrm{g})\) in air at equilibrium, if partial pressure of \(\mathrm{O}_{2}(\mathrm{~g})\) in air at equilibrium is \(0.2 \mathrm{~atm}\), would be (a) \(1.9 \times 10^{4} \mathrm{~atm}\) (b) \(1.9 \times 10^{-4} \mathrm{~atm}\) (c) \(2.08 \times 10^{4} \mathrm{~atm}\) (d) \(2.08 \times 10^{-4} \mathrm{~atm}\)

For the reaction (1) and (2) \(\mathrm{A} \rightleftharpoons(\mathrm{g})\) \(\mathrm{B}(\mathrm{g})+\mathrm{C}(\mathrm{g})\) \(\mathrm{X} \rightleftharpoons{\rightleftharpoons}(\mathrm{g})\) \(2 \mathrm{Y}(\mathrm{g}) \quad\) (ii) Given, \(K_{p_{1}}: K_{p_{2}}=9: 1 .\) If degree of dissociation of \(A\) (g) and \(X\) (g) are same then the ratio of total pressure in equilibrium (1) and ( 2 ) will be (a) \(36: 1\) (b) \(0.5: 1\) (c) \(1: 1\) (d) \(3: 1\)

For the reaction (i) and (ii) \(\mathrm{A}(\mathrm{g}) \rightleftharpoons \mathrm{B}(\mathrm{g})+\mathrm{C}(\mathrm{g})\) \(\mathrm{X}(\mathrm{g}) \rightleftharpoons 2 \mathrm{Y}(\mathrm{g})\) Given, \(\mathrm{K}_{\mathrm{P}_{1}}: \mathrm{K}_{\mathrm{P}_{\mathbf{3}}}=9: 1\) If the degree of dissociation of \(\mathrm{A}(\mathrm{g})\) and \(\mathrm{X}(\mathrm{g})\) be same then the total pressure at equilibrium (i) and (ii) are in the ratio: (a) \(3: 1\) (b) \(36: 1\) (c) \(1: 1\) (d) \(0.5: 1\)

For the reaction \(\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{H}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_{3}(\mathrm{~g})\) at \(500^{\circ} \mathrm{C}\), the value of \(\mathrm{K}_{n}\) is \(1.44 \times 10^{-5}\) when the partial pressures are measured in atmosphere. The value of \(\mathrm{K}_{\mathrm{c}}\) with concentration in \(\mathrm{mol} \mathrm{L}^{-1}\) is (a) \(\frac{1.44 \times 10^{-5}}{(8.314 \times 773)^{-2}}\) (b) \(\frac{1.44 \times 10^{-5}}{(0.082 \times 500)^{-2}}\) (c) \(\frac{1.44 \times 10^{-5}}{(0.082 \times 773)^{-2}}\) (d) \(\frac{1.44 \times 10^{-5}}{(0.082 \times 773)^{-2}}\)

At \(550 \mathrm{~K}\), the \(\mathrm{Kc}\) for the following reaction is \(10^{4}\) \(\mathrm{mol}^{-1} \mathrm{~L}\) \(\mathrm{X}(\mathrm{g})+\mathrm{Y}(\mathrm{g}) \rightleftharpoons \mathrm{Z}(\mathrm{g})\) At equilibrium, it was observed that \([\mathrm{X}]=\frac{1}{2}[\mathrm{Y}]=\frac{1}{2}[\mathrm{Z}]\) What is the value of \([\mathrm{Z}]\) at equilibrium? (a) \(10^{-4} \mathrm{~mol} \mathrm{~L}^{-1}\) (b) \(2 \times 10^{-4} \mathrm{~mol} \mathrm{~L}^{-1}\) (c) \(2 \times 10^{4} \mathrm{~mol} \mathrm{~L}^{-1}\) (d) \(10^{4} \mathrm{~mol} \mathrm{~L}^{-1}\)

One mole of \(\mathrm{N}_{2} \mathrm{O}_{4}(\mathrm{~g})\) at \(300 \mathrm{~K}\) is kept in a closed container under one atmospheric pressure. It is heated to \(600 \mathrm{~K}\) when \(20 \%\) by mass of \(\mathrm{N}_{2} \mathrm{O}_{4}(\mathrm{~g})\) decomposes to \(\mathrm{NO}_{2}(\mathrm{~g})\). The resultant pressure is (a) \(1.0 \mathrm{~atm}\) (b) \(2.4 \mathrm{~atm}\) (c) \(2.0 \mathrm{~atm}\) (d) \(1.2 \mathrm{~atm}\)

The equilibrium constant \((\mathrm{K})\) of the reaction, \(\mathrm{A}+\mathrm{B} \rightleftharpoons \mathrm{C}+\mathrm{D}\) at \(298 \mathrm{~K}\) is 100 . If the rate con- stant of the forward reaction is \(4 \times 10^{5}\), the rate constant of the reverse reaction is (a) 4 (b) \(4 \times 10^{2}\) (c) \(4 \times 10^{3}\) (d) \(4 \times 10^{5}\)

One mole of \(\mathrm{N}_{2} \mathrm{O}_{4}\) (g) at \(310 \mathrm{~K}\) is \(25 \%\) dissociated at 1 atm pressure. The percentage dissociation at \(0.1 \mathrm{~atm}\) and \(310 \mathrm{~K}\) is (a) \(25 \%\) (b) \(50 \%\) (c) \(76 \%\) (d) \(63 \%\)

\(2 \mathrm{NOBr} \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})+\mathrm{Br}_{2}(\mathrm{~g}) .\) If \(\mathrm{NOBr}\) is dissoci- ated to the extent of \(20 \%\) at \(\mathrm{T} \mathrm{K}\) and a total pressure of 1.1 atm, then \(K_{p}\) in atm for the formation of NOBr is (a) 160 (b) \(\frac{1}{160}\) (c) \(\frac{1}{120}\) (d) 120

\(\mathrm{K}_{\mathrm{p}}\) has the value of \(10^{-6} \mathrm{~atm}^{3}\) and \(10^{-4} \mathrm{~atm}^{3}\) at \(298 \mathrm{~K}\) and \(323 \mathrm{~K}\) respectively for the reaction \(\mathrm{CuSO}_{A} \cdot 3 \mathrm{H}_{2} \mathrm{O}(\mathrm{s}) \rightleftharpoons \mathrm{CuSO}_{4}(\mathrm{~s})+3 \mathrm{H}_{2} \mathrm{O}(\mathrm{g})\) \(\Delta \mathrm{H}^{\circ}\) for the reaction is: (a) \(7.7 \mathrm{~kJ} / \mathrm{mol}\) (b) \(-147.41 \mathrm{~kJ} / \mathrm{mol}\) (c) \(147.41 \mathrm{~kJ} / \mathrm{mol}\) (d) None of these

A flask containing \(0.5\) atm pressure of \(\mathrm{A}_{2}(\mathrm{~g})\), some solid AB added into flask which undergoes dissociation according to \(2 \mathrm{AB}(\mathrm{s})=\mathrm{A}_{2}(\mathrm{~g})+\mathrm{B}_{2}(\mathrm{~g}) \mathrm{K}_{\mathrm{P}}=\) \(0.06 \mathrm{~atm}^{2}\). The total pressure (in atm) at equilibrium is: (a) \(0.70\) (b) \(0.6\) (c) \(0.10\) (d) None of these

In a system \(\mathrm{A}(\mathrm{s}) \rightleftharpoons 2 \mathrm{~B}(\mathrm{~g})+3 \mathrm{C}(\mathrm{g})\) If the concentration of \(\mathrm{C}\) at equilibrium is increased by a factor of 2, it will cause the equilibrium concentration of \(\mathrm{B}\) to change to (a) One half of its original value (b) Two times the original value (c) \(\frac{1}{2 \sqrt{2}}\) times the original value (d) \(2 \sqrt{2}\) times its original value

\(\frac{\mathrm{K}_{\mathrm{P}}}{\mathrm{K}_{c}}\) for the reaction \(\mathrm{CO}(\mathrm{g})+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons \mathrm{CO}_{2}(\mathrm{~g})\) will be (a) \(\sqrt{\mathrm{RT}}\) (b) \(\mathrm{RT}\) (c) \(\frac{1}{\sqrt{\mathrm{RT}}}\) (d) 1

At \(25^{\circ} \mathrm{C}\), the standard emf of a cell having reaction involving two electron exchange is found to be \(0.295 \mathrm{~V}\). The equilibrium constant of the reaction is approximately (a) \(9.50 \times 10^{9}\) (b) \(1 \times 10^{10}\) (c) 10 (d) \(9.51 \times 10^{7}\)

A \(250 \mathrm{ml}\) flask containing \(\mathrm{NO}(\mathrm{g})\) at \(0.46 \mathrm{~atm}\) is connected to a \(100 \mathrm{ml}\) flask containing oxygen gas at \(0.86\) atm by means of a stop cock at \(350 \mathrm{~K}\). the gases are mixed by opening the stop cock where the following equilibrium is established. $$ \underset{\mathrm{g}}{2 \mathrm{NO}}+\mathrm{O}_{2} \rightarrow 2 \mathrm{NO}_{2}=\mathrm{N}_{2} \mathrm{O}_{4} $$ The first reaction is complete while the second is at equilibrium. If the total pressure is \(0.37 \mathrm{~atm}, \mathrm{~K}_{\mathrm{p}}\) is (a) \(0.645 \mathrm{~atm}^{-1}\) (b) \(1.290 \mathrm{~atm}^{-1}\) (c) \(20 \mathrm{~atm}^{-1}\) (d) \(5.46 \mathrm{~atm}^{-1}\)

The equilibrium constants for the reactions \(\mathrm{N}_{2}+3 \mathrm{H}_{2} \rightleftharpoons 2 \mathrm{NH}_{3}\) and \(\frac{1}{2} \mathrm{~N}_{2}+\frac{3}{2} \mathrm{H}_{2} \rightleftharpoons \mathrm{NH}_{3}\) are \(K_{1}\) and \(K_{2}\) respectively. The correct relationship between \(\mathrm{K}_{1}\) and \(\mathrm{K}\), is (a) \(\mathrm{K}_{1}=\frac{\mathrm{K}_{2}}{2}\) (b) \(\mathrm{K}_{2}=\sqrt{\mathrm{K}_{\mathrm{i}}}\) (c) \(\mathrm{K}_{2}=\mathrm{K}_{1}{\underline{\phantom{xx}}}^{2}\) (d) \(\mathrm{K}_{1}=\mathrm{K}_{2}\)

The coagulation of \(100 \mathrm{ml}\) of colloidal solution of gold is completely prevented by addition of \(0.25 \mathrm{~g}\) of a substance " \(X\) "to it before addition of \(10 \mathrm{ml}\) of \(10 \% \mathrm{NaCl}\) solution. The gold number of " \(\mathrm{X}\) " is (a) 25 (b) 250 (c) \(2.5\) (d) \(0.25\)

One mole of \(\mathrm{N}_{2}(\mathrm{~g})\) is mixed with \(2 \mathrm{moles}\) of \(\mathrm{H}_{2}(\mathrm{~g})\) in a 4 litre vessel. If \(50 \%\) of \(\mathrm{N}_{2}(\mathrm{~g})\) is converted to \(\mathrm{NH}_{3}(\mathrm{~g})\) by the following reaction: \(\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{H}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_{3}(\mathrm{~g})\) What will be the value of \(K_{c}\) for the following equilibrium? $$ \mathrm{NH}_{3}(\mathrm{~g}) \rightleftharpoons \frac{1}{2} \mathrm{~N}_{2}(\mathrm{~g})+\frac{3}{2} \mathrm{H}_{2}(\mathrm{~g}) $$ (a) 256 (b) 16 (c) \(\frac{1}{16}\) (d) None of these

If \(\mathrm{pKa}=-\log \mathrm{K}=4\) and \(\mathrm{K}=\mathrm{Cx}^{2}\) then van't Hoff factor weak monobasic acid when \(\mathrm{C}=0.01 \mathrm{M}\) is (a) \(1.02\) (b) \(1.01\) (c) \(1.20\) (d) \(1.10\)

The equilibrium constant \(\left(\mathrm{K}_{\mathrm{p}}\right)\) for the decomposition of water \(\mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \rightarrow \mathrm{H}_{2}(\mathrm{~g})+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g})\) Is given by (a) \(\mathrm{K}_{\mathrm{p}}=\frac{\alpha^{3} \mathrm{P}^{\frac{1}{2}}}{\sqrt{2}}\) (b) \(\mathrm{K}_{\mathrm{p}}=\frac{\alpha^{3} \mathrm{P}^{\frac{3}{2}}}{(1-\alpha)(2+\alpha)^{\frac{1}{2}}}\) (c) \(\mathrm{K}_{\mathrm{P}}=\frac{\alpha^{3} \mathrm{P}^{\frac{1}{2}}}{(1+\alpha)(2-\alpha)^{\frac{1}{2}}}\) (d) \(\mathrm{K}_{\mathrm{p}}=\frac{\alpha^{3 / 2} \mathrm{P}^{1 / 2}}{(1-\alpha)(2+\alpha)^{1 / 2}}\) Where \(\alpha\) is the degree of dissociation and \(\mathrm{p}\) is the pressure of the reaction mixture at equilibrium.

Which of the following will favour the formation of \(\mathrm{NH}_{3}\) by Haber's Process? (a) Increase of temperature (b) Increase of pressure (c) Addition of catalyst (d) Addition of promoter

When solid \(\mathrm{NaNO}_{3}\) is heated in a closed vessel, \(\mathrm{O}_{2}\) is liberated and solid \(\mathrm{NaNO}_{2}\) is left behind. At equilibrium (a) Addition of \(\mathrm{NaNO}_{2}\) favours reverse reaction. (b) Addition of \(\mathrm{NaNO}_{3}\) favours forward reaction. (c) Increasing the pressure favours reverse reaction. (d) Increasing the temperature favours forward reaction.

\(\mathrm{PCl}_{5}(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g})\) At constant temperature, forward reaction is favoured by (a) introducing inert gas at constant volume (b) introducing inert gas at constant pressure (c) introducing chlorine gas at constant volume (d) increasing the volume of the container

For the reaction \(2 \mathrm{HI}(\mathrm{g})=\mathrm{H}_{2}(\mathrm{~g})+\mathrm{I}_{2}(\mathrm{~g})\) if the degree of dissociation is \(\alpha\) and \(\mathrm{K}_{\mathrm{p}}\) is the equilibrium constant, then (a) \(\alpha=\frac{\sqrt{2 \mathrm{~K}_{\mathrm{p}}}}{1+\sqrt{2 \mathrm{k}_{\mathrm{p}}}}\) (b) \(\alpha=\frac{2 \sqrt{K_{\mathrm{P}}}}{1+2 \sqrt{\mathrm{K}_{\mathrm{p}}}}\) (c) \(\sqrt{2 \mathrm{~K}_{\mathrm{p}}}=\left(\frac{\alpha}{1-\alpha}\right)\) (d) \(2 \sqrt{K_{\mathrm{p}}}=\left(\frac{\alpha}{1-\alpha}\right)\)

If the concentrations of two monobasic acids are same, their relative strengths can be compared by (a) \(\left(\frac{K_{1}}{K_{2}}\right)\) (b) \(\left(\frac{\alpha_{1}}{\alpha_{2}}\right)\) (c) \(\left(\sqrt{\frac{K_{1}}{K_{2}}}\right)\) (d) \(\frac{\left[\mathrm{H}^{+}\right]_{1}}{\left[\mathrm{H}^{+}\right]_{2}}\)

Match the following Column-I (a) \(\mathrm{N}_{2} \mathrm{O}_{4}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}_{2}(\mathrm{~g})\) (b) \(\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{H}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_{3}(\mathrm{~g})\) \(\Delta \mathrm{H}=-\mathrm{Q} \mathrm{cal}\) (c) \(2 \mathrm{CO}_{2}(\mathrm{~g})=2 \mathrm{CO}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g})\) \(\Delta \mathrm{H}=+\mathrm{Q} \mathrm{cal}\) (d) \(\mathrm{H}_{2}(\mathrm{~g})+\mathrm{I}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{HI}(\mathrm{g})\) \(\Delta \mathrm{H}=-\mathrm{Q} \mathrm{cal}\) Column-II (p) Low temperature; high pressure (q) High temperature (r) \(\mathrm{K}_{\mathrm{P}}=\frac{4 \mathrm{x}^{2} \mathrm{P}}{\mathrm{a}^{2}-\mathrm{x}^{2}}\) (s) \(K_{p}=K_{c}\) (t) \(\frac{K_{\text {P }}}{K_{c}}=(R T)^{-2}\)

Match the following Column-I (a) \(\mathrm{H}_{2}(\mathrm{~g})+\mathrm{I}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{HI}(\mathrm{g})\) (b) \(\mathrm{CaCO}_{3}(\mathrm{~s}) \rightleftharpoons \mathrm{CaO}(\mathrm{s})+\mathrm{CO}_{2}(\mathrm{~g})\) (c) \(\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{H}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_{3}(\mathrm{~g})\) (d) \(\mathrm{PCl}_{5}(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g})\) Column-II (p) Unaffected by inert gas addition at constant volume (q) Forward shift by rise in pressure (r) Unaffected by increase in pressure (s) Backward shift by rise in pressure (t) reaction has \(\Delta n_{8}>0\)

Assertion: The equilibrium of \(\mathrm{A}(\mathrm{g}) \rightleftharpoons \mathrm{B}(\mathrm{g})+\mathrm{C}(\mathrm{g})\) is not affected by changing volume of the system. Reason: \(\mathrm{K}_{\mathrm{c}}\) for the reaction does not depend on volume of the container.

Assertion: Adding an inert gas todissociation equilibrium of gaseous \(\mathrm{N}_{2} \mathrm{O}_{4}\) at constant pressure and temperature increases the dissociation. Reason: Molar concentration of the reactants and products decreases on the addition of inert gas.

For the reaction, \(\mathrm{N}_{2} \mathrm{O}_{4}(\mathrm{~g})=2 \mathrm{NO}_{2}(\mathrm{~g})\), the degree of dissociation at equilibrium is \(0.2\) at 1 atm pressure. The reciprocal of equilibrium constant \(\left(\frac{1}{\mathrm{~K}_{\mathrm{P}}}\right)\) is \(\mathrm{atm}^{-1} .\)

At a particular temperature \(\mathrm{PCl}_{5}\) (g) undergoes \(50 \%\) dissociation. The equilibrium constant for \(\mathrm{PCl}_{5}(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g})\) is \(2 \mathrm{~atm}\). The pres- sure of the equilibrium mixture is atm.

The following mechanism proposed for a reaction \(2 \mathrm{~A}+\mathrm{B} \rightarrow \mathrm{D}+\mathrm{E}\) is as \(\mathrm{A}+\mathrm{B} \longrightarrow \mathrm{C}\) (fast) \(\mathrm{A}+\mathrm{C} \rightarrow \mathrm{E}+\mathrm{D}\) (slow) The order of reaction is

The degree of dissociation of HI at a particular temperature is \(0.8\). Calculate the volume (in litres) of \(1.6\) M \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) required to neutralize the iodine present in a equilibrium mixture of a reaction when 2 mole each of \(\mathrm{H}_{2}\) and \(\mathrm{I}_{2}\) are heated in a closed vessel of \(2 \mathrm{~L}\).

For the equilibrium \(\mathrm{AB}(\mathrm{g}) \rightleftharpoons \mathrm{A}(\mathrm{g})+\mathrm{B}(\mathrm{g})\), at a given temperature \(\frac{1}{3}\) rd of \(\mathrm{AB}\) is dissociated then \(\frac{\mathrm{P}}{\mathrm{K}_{\mathrm{p}}}\) will be numerically equal to

For the following reaction in gaseous phase [2002] \(\mathrm{CO}+1 / 2 \mathrm{O}_{2} \rightleftharpoons \mathrm{CO}_{2}\) \(\mathrm{K} / \mathrm{K}_{\mathrm{p}}\) is (a) \((\mathrm{RT})^{1 / 2}\) (b) \((\mathrm{RT})^{-1 / 2}\) (c) (RT) (d) \((\mathrm{RT})^{-1}\)

One of the following equilibria is not affected by change in volume of the flask: (a) \(\mathrm{PCl}_{5}(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{~g}) \mathrm{Cl}_{2}(\mathrm{~g})\) (b) \(\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{H}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NH}_{3}(\mathrm{~g})\) (c) \(\mathrm{N}_{2}(\mathrm{~g})+\mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})\) (d) \(\mathrm{SO}_{2} \mathrm{Cl}_{2}(\mathrm{~g}) \rightleftharpoons \mathrm{SO}_{2}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g})\)

Consider the reaction equilibrium, \(2 \mathrm{SO}_{2}(\mathrm{~g})+\mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{SO}_{3}(\mathrm{~g}) ; \Delta \mathrm{H}^{\circ}=-198 \mathrm{~kJ}\) on the basis of Le Chatelier's principle, the condition favourable for the forward reaction is (a) lowering of temperature as well as pressure (b) increasing temperature as well as pressure (c) lowering the temperature and increasing the pressure (d) any value of temperature and pressure

For the reaction equilibrium, \(\mathrm{N}_{2} \mathrm{O}_{4}(\mathrm{~g})=2 \mathrm{NO}(\mathrm{g})\) the concentrations of \(\mathrm{N}_{2} \mathrm{O}_{4}\) and \(\mathrm{NO}_{2}\) at equilibrium are \(4.8 \times 10^{-2}\) and \(1.2 \times 10^{-2} \mathrm{~mol} \mathrm{~L}^{-1}\) respectively. The value of \(\mathrm{K}\) for the reaction is (b) \(3 \times 10^{-1} \mathrm{~mol} \mathrm{~L}^{-1}\) (a) \(3.3 \times 10^{2} \mathrm{~mol} \mathrm{~L}^{-1}\) (c) \(3 \times 10^{-3} \mathrm{~mol} \mathrm{~L}^{-1}\) (d) \(3 \times 10^{3} \mathrm{~mol} \mathrm{~L}^{-1}\)

What is the equilibrium expression for the reaction \(\mathrm{P}_{4}(\mathrm{~s})+5 \mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons \mathrm{P}_{4} \mathrm{O}_{10}(\mathrm{~s}) ?\) (a) \(\mathrm{K}_{c}=\frac{\left[\mathrm{P}_{4} \mathrm{O}_{10}\right]}{5\left[\mathrm{P}_{4}\right]\left[\mathrm{O}_{2}\right]^{5}}\) (b) \(\mathrm{K}_{\mathrm{c}}=\frac{1}{\left[\mathrm{O}_{2}\right]^{5}}\) (c) \(K_{c}=\frac{\left[P_{4} O_{10}\right]}{\left[P_{4}\right]\left[O_{2}\right]^{5}}\) (d) \(\mathrm{K}_{\mathrm{c}}=\left[\mathrm{O}_{2}\right]^{5}\)

The equilibrium constant for the reaction, \(\mathrm{N}_{2}(\mathrm{~g})+\mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})\) At temperature \(\mathrm{T}\) is \(4 \times 10^{-4} .\) The value of \(\mathrm{K}_{c}\) for the reaction \(\mathrm{NO}(\mathrm{g}) \rightleftharpoons 1 / 2 \mathrm{~N}_{2}(\mathrm{~g})+1 / 2 \mathrm{O}_{2}(\mathrm{~g})\) at the same temperature is (a) \(4 \times 10^{-6}\) (b) \(2.5 \times 10^{2}\) (c) \(0.02\) (d) 50

Consider an endothermic reaction \(\mathrm{X} \longrightarrow \mathrm{Y}\) with the activation energies \(E_{b}\) and \(E_{f}\) for the backward and forward reactions, respectively. In general (a) \(\mathrm{E}_{\mathrm{b}}<\mathrm{E}_{\mathrm{f}}\) (b) \(E_{b}>E_{f}\) (c) \(\mathrm{E}_{\mathrm{b}}=\mathrm{E}_{\mathrm{f}}\) (d) there is no definite relation between \(\mathrm{E}_{\mathrm{b}}\) and \(\mathrm{E}_{\mathrm{f}}\)

For the reaction, \(2 \mathrm{NO}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}(\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g})\) \(\left(\mathrm{K}_{c}=1.8 \times 10^{-6}\right.\) at \(\left.184^{\circ} \mathrm{C}\right)\) \((\mathrm{R}=0.0831 \mathrm{~kJ} /(\mathrm{mol} \mathrm{K}))\) when \(\mathrm{K}_{\mathrm{p}}\) and \(\mathrm{K}_{c}\) are compared at \(184^{\circ} \mathrm{C}\) it is found that (a) \(\mathrm{K}_{\mathrm{p}}\) is greater than \(\mathrm{K}_{\mathrm{c}}\) (b) \(\mathrm{K}_{\mathrm{p}}\) is less than \(\mathrm{K}_{\mathrm{c}}\) (c) \(\mathrm{K}_{\mathrm{p}}=\mathrm{K}_{\mathrm{c}}\) (d) whether \(\mathrm{K}_{\mathrm{p}}\) is greater than, less than or equal to \(\mathrm{K}_{c}\) depends upon the total gas pressure

An amount of solid \(\mathrm{NH}_{4} \mathrm{HS}\) in placed in a flask already containing ammonia gas at a certain temperature and \(0.50\) atm pressure. Ammonium hydrogen sulphide decomposes to yield \(\mathrm{NH}_{3}\) and \(\mathrm{H}_{2} \mathrm{~S}\) gases in the flask. When the decomposition reaction reaches equilibrium, the total pressure is the flask rises to \(0.84 \mathrm{~atm}\), the equilibrium constant for NH HS decomposition at this temperature is (a) \(0.30\) (b) \(0.18\) (c) \(0.17\) (d) \(0.11\)

The exothermic formation of \(\mathrm{ClF}_{3}\) is represented by the equation \(\mathrm{Cl}_{2}(\mathrm{~g})+3 \mathrm{~F}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{ClF}_{3}(\mathrm{~g}) ; \Delta \mathrm{H}=-329 \mathrm{~kJ}\) Which of the following will increase the quantity of \(\mathrm{CIF}_{3}\) in an equilibrium mixture of \(\mathrm{Cl}_{2}, \mathrm{~F}_{2}\) and \(\mathrm{ClF}_{3} ?\) (a) increasing the temperature (b) removing \(\mathrm{Cl}_{2}\) (c) increasing the volume of the container (d) adding \(\mathrm{F}_{2}\)

Phosphorous pentachloride dissociates as follows, in a closed reaction vessel \(\mathrm{PCI}_{5}(\mathrm{~g}) \longrightarrow \mathrm{PCl}_{3}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g})\) If total pressure at equilibrium of the reaction mixture is \(\mathrm{P}\) and degree of dissociation of \(\mathrm{PCl}_{5}\) is \(\mathrm{x}\), the partial pressure of \(\mathrm{PCl}_{3}\) will be (a) \(\left(\frac{x}{(x+1)}\right) \mathrm{P}\) (b) \(\left(\frac{2 x}{(x-1)}\right) \mathrm{P}\) (c) \(\left(\frac{x}{(x-1)}\right) \mathrm{P}\) (d) \(\left(\frac{x}{(1-x)}\right) P\)

The equilibrium constant for the reaction \(\mathrm{SO}_{3}(\mathrm{~g}) \rightleftharpoons \mathrm{SO}_{2}(\mathrm{~g})+1 / 2 \mathrm{O}_{2}(\mathrm{~g})\) is \(\mathrm{K}_{c}=4.9 \times 10^{-2} .\) the value of \(\mathrm{K}_{\mathrm{c}}\) for the reaction \(2 \mathrm{SO}_{2}\) \((\mathrm{g})+\mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons 2 \mathrm{SO}_{3}(\mathrm{~g})\) will be (a) 416 (b) \(2.40 \times 10^{-3}\) (c) \(9.8 \times 10^{-2}\) (d) \(4.9 \times 10^{-2}\)

The equilibrium constants \(\mathrm{K}_{\mathrm{P}}\) and \(\mathrm{K}_{\mathrm{P}}\) for the reactions \(\mathrm{X} \longrightarrow 2 \mathrm{Y}\) and \(\mathrm{Z} \rightleftharpoons \mathrm{P}+\mathrm{Q}\), respectively are in the ratio of \(1: 9 .\) If the degree of dissociation of \(\mathrm{X}\) and \(Z\) be equal then the ratio of total pressure at these equilibria is (a) \(1: 36\) (b) \(1: 1\) (c) \(1: 3\) (d) \(1: 9\)

For the following three reactions \(\mathrm{A}\), B and \(\mathrm{C}\), equilibrium constants are given: (a) \(\mathrm{CO}(\mathrm{g})+\mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \rightleftharpoons \mathrm{CO}_{2}(\mathrm{~g})+\mathrm{H}_{2}(\mathrm{~g}) ; \mathrm{K}_{1}\) (b) \(\mathrm{CH}_{4}(\mathrm{~g})+\mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \rightleftharpoons \mathrm{CO}(\mathrm{g})+3 \mathrm{H}_{2}(\mathrm{~g}) ; \mathrm{K}_{2}\) (c) \(\mathrm{CH}_{4}(\mathrm{~g})+2 \mathrm{H}_{2} \mathrm{O}(\mathrm{g}) \rightleftharpoons \mathrm{CO}_{2}(\mathrm{~g})+4 \mathrm{H}_{2}(\mathrm{~g}) ; \mathrm{K}_{3}\) Which of the following relation is correct? (a) \(\mathrm{K}_{1} \sqrt{\mathrm{K}}_{2}=\mathrm{K}_{2}\) (b) \(\mathrm{K}_{2} \mathrm{~K}_{3}=\mathrm{K}_{1}\) (c) \(\mathrm{K}_{3}=\mathrm{K}_{1} \mathrm{~K}_{2}\) (d) \(\mathrm{K}_{3} \cdot \mathrm{K}_{2}^{3}=\mathrm{K}_{1}^{2}\)