Chemical Equilibrium Test 2

Total Questions:50 Total Time: 75 Min



Questions 1 of 50

Question:For the reaction \({H_2}(g) + {I_2}(g)\) \( \Leftrightarrow \)\(2HI(g)\), the equilibrium constant changes with

Answers Choices:

Total pressure


The amounts of \({H_2}\) and \({I_2}\) taken


Questions 2 of 50

Question:Calculate \(\Delta G^\circ \)for conversion of oxygen to ozone \(3/2\;{O_2}(g) \to {O_3}(g)\)at 298 K, if \({K_p}\)for this conversion is \(2.47 \times {10^{ - 29}}\)

Answers Choices:

\(163\;kJ\;mo{l^{ - 1}}\)

\(2.4 \times {10^2}\;kJ\;mo{l^{ - 1}}\)

\(1.63\;kJ\;mo{l^{ - 1}}\)

\(2.38 \times {10^6}\;kJ\;mo{l^{ - 1}}\)

Questions 3 of 50

Question:In any chemical reaction, equilibrium is supposed to be establish when

Answers Choices:

Mutual opposite reactions undergo

Concentration of reactants and resulting products are equal

Velocity of mutual reactions become equal

The temperature of mutual opposite reactions become equal

Questions 4 of 50

Question:\(C{H_3}COO{H_{(l)}} + {C_2}{H_5}O{H_{(l)}}\) ? \(C{H_3}COO{C_2}{H_{5\,(l)}} + {H_2}{O_{(l)}}\) In the above reaction, one mole of each of acetic acid and alcohol are heated in the presence of little conc. \({H_2}S{O_4}\). On equilibrium being attained

Answers Choices:

1 mole of ethyl acetate is formed

2 mole of ethyl acetate are formed

1/2 moles of ethyl acetate is formed

2/3 moles of ethyl acetate is formed

Questions 5 of 50

Question:If the equilibrium constant of the reaction \(2HI\) \( \Leftrightarrow \) \({H_2} + {I_2}\) is 0.25, then the equilibrium constant of the reaction \({H_2} + {I_2}\) \( \Leftrightarrow \) \(2HI\) would be

Answers Choices:





Questions 6 of 50

Question:For \({N_2} + 3{H_2}\) \( \Leftrightarrow \) \(2N{H_3} + \) heat

Answers Choices:

\({K_p} = {K_c}(RT)\)

\({K_p} = {K_c}(RT)\)

\({K_p} = {K_c}\,{(RT)^{ - 2}}\)

\({K_p} = {K_c}\,{(RT)^{ - 1}}\)

Questions 7 of 50

Question:For the following gaseous reaction \({H_2} + {I_2}\) \( \Leftrightarrow \) \(2HI\), the equilibrium constant

Answers Choices:

\({K_p} > {K_c}\)

\({K_p} < {K_c}\)

\({K_p} = {K_c}\)

\({K_p} = 1/{K_c}\)

Questions 8 of 50

Question:For the reaction \(2N{O_{2(g)}}\) \( \Leftrightarrow \) \(2N{O_{(g)}} + {O_{2(g)}}\)\(({K_c} = 1.8 \times {10^{ - 6}}\,{\rm{at}}\,\,184^\circ C)\)\((R = 0.0831\,kJ/\,(mol.\,K))\)When \({K_p}\) and \({K_c}\) are compared at 184°C it is found that

Answers Choices:

\({K_p}\) is greater than \({K_c}\)

\({K_p}\) is less than \({K_c}\)

\({K_p} = {K_e}\)

Whether \({K_p}\) is greater than, less than or equal to \({K_c}\) depends upon the total gas pressure

Questions 9 of 50

Question:In equilibrium \(C{H_3}COOH + {H_2}O\) \( \Leftrightarrow \)\(C{H_3}COO + H_3^ + O\) The equilibrium constant may change when

Answers Choices:

\(C{H_3}CO{O^ - }\) are added

\(C{H_3}COOH\) is added

Catalyst is added

Mixture is heated

Questions 10 of 50

Question:At 490°C, the equilibrium constant for the synthesis of HI is 50, the value of K for the dissociation of HI will be

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Questions 11 of 50

Question:In which of the following case Kp is less than Kc

Answers Choices:

\({H_2} + C{l_2}\) \( \Leftrightarrow \)\(2HCl\)

\(2S{O_2} + {O_2}\) \( \Leftrightarrow \)\(2S{O_3}\)

\({N_2} + {O_2}\) \( \Leftrightarrow \)\(2NO\)

\(PC{l_5}\) \( \Leftrightarrow \)\(PC{l_3} + C{l_2}\)

Questions 12 of 50

Question:\(CaC{O_{3(s)}}\) \( \Leftrightarrow \)\(Ca{O_{(s)}} + C{O_{2(g)}}\) which of the following expression is correct

Answers Choices:

\({K_P} = ({P_{CaO}} + {P_{C{O_2}}}/{P_{CaC{O_3}}})\)

\({K_P} = {P_{C{O_2}}}\)

\({K_P} \times ({P_{CaO}} \times {P_{C{O_2}}}).{P_{CaC{O_3}}}\)


Questions 13 of 50

Question:For the reaction, \(PC{l_{3(g)}}\)+\(C{l_{2(g)}}\) \( \Leftrightarrow \)\(PC{l_{5(g)}}\), the value of \({K_c}\) at 250°C is 26. The value of \({K_p}\) at this temperature will be

Answers Choices:





Questions 14 of 50

Question:A tenfold increase in pressure on the reaction \({N_{2(g)}}\)\( + 3{H_{2(g)}}\) \( \Leftrightarrow \)\(2N{H_{3(g)}}\) at equilibrium, makes \({K_p}\)

Answers Choices:


Two times

Four times

Ten times

Questions 15 of 50

Question:If equilibrium constant for reaction \(2AB\) \( \Leftrightarrow \)\({A_2} + {B_2}\), is 49, then the equilibrium constant for reaction AB \( \Leftrightarrow \) \(\frac{1}{2}{A_2} + \frac{1}{2}{B_2}\), will be

Answers Choices:





Questions 16 of 50

Question:In the manufacture of ammonia by Haber's process, \({N_{2(g)}} + 3{H_2}\) \( \Leftrightarrow \)\(2N{H_{3(g)}} + 92.3kJ\),which of the following conditions is unfavourable

Answers Choices:

Increasing the temperature

Increasing the pressure

Reducing the temperature

Removing ammonia as it is formed

Questions 17 of 50

Question:\(N{H_4}COON{H_{2(s)}}\) \( \Leftrightarrow \) \(2N{H_{3(g)}} + C{O_{2(g)}}\) if equilibrium pressure is 3 atm for the above reaction \({K_p}\) for the reaction is

Answers Choices:





Questions 18 of 50

Question:For the system \(3A + 2B\) \( \Leftrightarrow \) \(C\), the expression for equilibrium constant is

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Questions 19 of 50

Question:In the reversible reaction \(A + B\) \ [ \Leftrightarrow \) \(C + D\), the concentration of each C and D at equilibrium was 0.8 mole/litre, then the equilibrium constant \({K_c}\) will be

Answers Choices:





Questions 20 of 50

Question:4 moles of A are mixed with 4 moles of B. At equilibrium for the reaction \(A + B\) \( \Leftrightarrow \)\(C + D\), 2 moles of C and D are formed. The equilibrium constant for the reaction will be

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Questions 21 of 50

Question:The decomposition of \({N_2}{O_4}\) to \(N{O_2}\) is carried out at \(280K\) in chloroform. When equilibrium has been established, 0.2 mol of \({N_2}{O_4}\) and \(2 \times {10^{ - 3}}\) mol of \(N{O_2}\) are present in 2 litre solution. The equilibrium constant for reaction \({N_2}{O_4}\) \( \Leftrightarrow \) \(2N{O_2}\) is

Answers Choices:

\(1 \times {10^{ - 2}}\)

\(2 \times {10^{ - 3}}\)

\(1 \times {10^{ - 5}}\)

\(2 \times {10^{ - 5}}\)

Questions 22 of 50

Question:Concentration of a gas is expressed in the following terms in the calculation of equilibrium constant

Answers Choices:

No. of molecules per litre

No. of grams per litre

No. of gram equivalent per litre

No. of molecules equivalent per litre

Questions 23 of 50

Question:The unit of equilibrium constant K for the reaction \(A + B\) \( \Leftrightarrow \) \(C\) would be

Answers Choices:

\(mol\,\,litr{e^{ - 1}}\)

\(litre\,\,mo{l^{ - 1}}\)



Questions 24 of 50

Question:In a reaction \(A + B\) \( \Leftrightarrow \) \(C + D\), the concentrations of A, B, C and D (in moles/litre) are 0.5, 0.8, 0.4 and 1.0 respectively. The equilibrium constant is

Answers Choices:




\(\infty \)

Questions 25 of 50

Question:An amount of solid \(N{H_4}HS\) is placed in a flask already containing ammonia gas at a certain temperature and 0.50 atm. pressure. Ammonium hydrogen sulphide decomposes to yield \(N{H_3}\) and \({H_2}S\) gases in the flask. When the decomposition reaction reaches equilibrium, the total pressure in the flask rises to 0.84 atm. The equilibrium constant for \(N{H_4}HS\) decomposition at this temperature is

Answers Choices:





Questions 26 of 50

Question:In the reaction \(A + 2B\) \( \Leftrightarrow \)\(2C\), if 2 moles of \(A,\,\,3.0\) moles of \(B\) and 2.0 moles of \(C\) are placed in a \(2.0\,\,l\) flask and the equilibrium concentration of \(C\) is 0.5 mole/\(l\). The equilibrium constant \(({K_c})\) for the reaction is

Answers Choices:





Questions 27 of 50

Question:In a \(500ml\) capacity vessel \(CO\) and \(C{l_2}\) are mixed to form \(COC{l_2}\). At equilibrium, it contains 0.2 moles of \(COC{l_2}\) and 0.1 mole of each of \(CO\) and \(C{O_2}\). The equilibrium constant \({K_c}\) for the reaction \(CO + C{l_2}\) \( \Leftrightarrow \)\(COC{l_2}\) is

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Questions 28 of 50

Question:A reaction is \(A + B \to C + D\). Initially we start with equal concentration of \(A\) and \(B\). At equilibrium we find the moles of \(C\) is two times of \(A\). What is the equilibrium constant of the reaction

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Questions 29 of 50

Question:For the reaction\({H_2} + {I_2} = 2HI\),the equilibrium concentration of \({H_{2\,}},\,{I_2}\) and \(HI\) are 8.0, 3.0 and 28.0 mol per litre respectively, the equilibrium constant of the reaction is

Answers Choices:





Questions 30 of 50

Question:Change in volume of the system does not alter the number of moles in which of the following equilibrium

Answers Choices:

\({N_{2(g)}} + {O_{2(g)}}\) \( \Leftrightarrow \) \(2N{O_{(g)}}\)

\(PC{l_{5(g)}}\) \( \Leftrightarrow \)\(PC{l_{3(g)}} + C{l_{2(g)}}\)

\({N_{2(g)}} + 3{H_2}_{(g)}\) \( \Leftrightarrow \)\(2N{H_{3(g)}}\)

\(S{O_2}C{l_{2(g)}}\) \( \Leftrightarrow \) \(S{O_{2(g)}} + C{l_{2(g)}}\)

Questions 31 of 50

Question:The rate of forward reaction is two times that of reverse reaction at a given temperature and identical concentration. Kequilibrium is

Answers Choices:





Questions 32 of 50

Question:Write the equilibrium constant K for\(C{H_3}COOH + {H_2}O = {H_3}{O^ + } + C{H_3}CO{O^ - }\)

Answers Choices:

\(K = \frac{{[{H_3}{O^ + }][{H_2}O]}}{{[C{H_3}CO{O^ - }][C{H_3}COOH]}}\)

\(K = \frac{{[{H_3}{O^ + }][C{H_3}CO{O^ - }]}}{{[{H_2}O][C{H_3}COOH]}}\)

\(K = \frac{{[{H_3}{O^ + }][{H_2}O]}}{{[C{H_3}COOH][C{H_3}CO{O^ - }]}}\)

\(K = \frac{{[{H_2}O][C{H_3}CO{O^ - }]}}{{[{H_2}O][C{H_3}COOH]}}\)

Questions 33 of 50

Question:The equilibrium constant for the reaction \({N_{2(g)}} + {O_{2(g)}}\) \( \Leftrightarrow \) \(2N{O_{(g)}}\) at temperature T is \(4 \times {10^{ - 4}}\). The value of \({K_c}\)for the reaction \(N{O_{(g)}}\) \( \Leftrightarrow \)\(\frac{1}{2}{N_{2(g)}} + \frac{1}{2}{O_{2(g)}}\) at the same temperature is

Answers Choices:

\(4 \times {10^{ - 4}}\)


\(2.5 \times {10^2}\)


Questions 34 of 50

Question:What is the equilibrium expression for the reaction \({P_{4(s)}} + 5{O_{2(g)}}\) \( \Leftrightarrow \) \({P_4}{O_{10(s)}}\)

Answers Choices:

\({K_c} = {[{O_2}]^5}\)

\({K_c} = [{P_4}{O_{10}}]/5[{P_4}][{O_2}]\)

\({K_c} = [{P_4}{O_{10}}]/[{P_4}]{[{O_2}]^5}\)

\({K_c} = 1/{[{O_2}]^5}\)

Questions 35 of 50

Question:In the reaction, \({H_2} + {I_2}\) \( \Leftrightarrow \)\(2HI\). In a 2 litre flask 0.4 moles of each \({H_2}\) and \({I_2}\) are taken. At equilibrium 0.5 moles of \(HI\) are formed. What will be the value of equilibrium constant, \({K_c}\)

Answers Choices:





Questions 36 of 50

Question:Theory of ‘active mass’ indicates that the rate of chemical reaction is directly proportional to the

Answers Choices:

Equilibrium constant

Properties of reactants

Volume of apparatus

Concentration of reactants

Questions 37 of 50

Question:The rate at which substances react depends on their

Answers Choices:

Atomic weight

Molecular weight

Equivalent weight

Active mass

Questions 38 of 50

Question:Which is false

Answers Choices:

The greater the concentration of the substances involved in a reaction, the lower the speed of the reaction

The point of dynamic equilibrium is reached when the reaction rate in one direction just balances the reaction rate in the opposite direction

The dissociation of weak electrolyte is a reversible reaction

The presence of free ions facilitates chemical changes

Questions 39 of 50

Question:In the reaction \(A(g) + 2B(g)\) \( \Leftrightarrow \) \(C(g) + Q\,kJ\), greater product will be obtained or the forward reaction is favoured by

Answers Choices:

At high temperature and high pressure

At high temperature and low pressure

At low temperature and high pressure

At low temperature and low pressure

Questions 40 of 50

Question:Following gaseous reaction is undergoing in a vessel \({C_2}{H_4} + {H_2}\) \( \Leftrightarrow \) \({C_2}{H_6}\); \(\Delta H = - 32.7\,Kcal\) Which will increase the equilibrium concentration of \({C_2}{H_6}\)

Answers Choices:

Increase of temperature

By reducing temperature

By removing some hydrogen

By adding some \({C_2}{H_6}\)

Questions 41 of 50

Question:The effect of increasing the pressure on the equilibrium \(2A + 3B\) \( \Leftrightarrow \)\(3A + 2B\) is

Answers Choices:

Forward reaction is favoured

Backward reaction is favoured

No effect

None of the above

Questions 42 of 50

Question:Suppose the reaction \(PC{l_{5(s)}}\) \( \Leftrightarrow \) \(PC{l_{3(s)}} + C{l_{2(g)}}\) is in a closed vessel at equilibrium stage. What is the effect on equilibrium concentration of \(C{l_{2(g)}}\) by adding \(PC{l_5}\) at constant temperature

Answers Choices:




Cannot be described without the value of \({K_p}\)

Questions 43 of 50

Question:In which of the following equilibrium reactions, the equilibrium would shift to the right, if total pressure is increased

Answers Choices:

\({N_2} + 3{H_2}\) \( \Leftrightarrow \) \(2N{H_3}\)

\({H_2} + {I_2}\) \( \Leftrightarrow \) \(2HI\)

\({H_2} + C{l_2}\) \( \Leftrightarrow \) \(2HCl\)

\({N_2}{O_4}\) \( \Leftrightarrow \) \(2NO\)

Questions 44 of 50

Question:In which of the following gaseous equilibrium an increase in pressure will increase the yield of the products

Answers Choices:

\(2HI\) \( \Leftrightarrow \)\({H_2} + {I_2}\)

\(2S{O_2} + {O_2}\) \( \Leftrightarrow \)\(2S{O_3}\)

\({H_2} + B{r_2}\) \( \Leftrightarrow \)\(2HBr\)

\({H_2}O + CO\) \( \Leftrightarrow \)\({H_2} + C{O_2}\)

Questions 45 of 50

Question:Which of the following information can be obtained on the basis of Le-chatelier's principle

Answers Choices:

Entropy change in a reaction

Dissociation constant of a weak acid

Equilibrium constant of a chemical reaction

Shift in equilibrium position on changing value of a constant

Questions 46 of 50

Question:The equilibrium \(2S{O_{2(g)}} + {O_{2(g)}}\) \( \Leftrightarrow \)\(2S{O_{3(g)}}\) shifts forward, if

Answers Choices:

A catalyst is used

An adsorbent is used to remove \(S{O_3}\) as soon as it is formed

Low pressure

Small amounts of reactants are used

Questions 47 of 50

Question:The equilibrium \(S{O_2}C{l_{2(g)}}\) \( \Leftrightarrow \)\(S{O_{2(g)}} + C{l_{2(g)}}\) is attained at 25°C in a closed container and an inert gas helium is introduced which of the following statement is correct

Answers Choices:

More chlorine is formed

Concentration of \(S{O_2}\) is reduced

More \(S{O_2}C{l_2}\) is formed

Concentration of \(S{O_2}C{l_2},\,S{O_2}\) and \(C{l_2}\) does not change

Questions 48 of 50

Question:\({H_{2(g)}}\)+ \({I_{2(g)}}\) \( \Leftrightarrow \)\(2H{I_{(g)}}\)In this reaction when pressure increases, the reaction direction

Answers Choices:

Does not change




Questions 49 of 50

Question:The rate of reaction of which of the following is not affected by pressure

Answers Choices:

\(PC{l_3} + C{l_2}\) \( \Leftrightarrow \)\(PC{l_5}\)

\({N_2} + 3{H_2}\) \( \Leftrightarrow \)\(2N{H_3}\)

\({N_2} + {O_2}\) \( \Leftrightarrow \) 2NO

\(2S{O_2} + {O_2}\) \( \Leftrightarrow \)\(2S{O_3}\)

Questions 50 of 50

Question:In the equilibrium N\(_{\rm{2}}\) + 3H\(_{\rm{2}}\) \( \Leftrightarrow \) 2NH\(_{\rm{2}}\) + 22 kcal, the formation of ammonia is favoured by

Answers Choices:

Increasing the pressure

Increasing the temperature

Decreasing the pressure

Adding ammonia