# Chemical Equilibrium Test 2

Total Questions:50 Total Time: 75 Min

Remaining:

## Questions 1 of 50

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

Total pressure

Catalyst

The amounts of $${H_2}$$ and $${I_2}$$ taken

Temperature

## 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 $$2.47 \times {10^{ - 29}}$$

$$163\;kJ\;mo{l^{ - 1}}$$

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

$$1.63\;kJ\;mo{l^{ - 1}}$$

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

## Questions 3 of 50

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

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

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

1

2

3

4

## Questions 6 of 50

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

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

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

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

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

## Questions 7 of 50

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

$${K_p} > {K_c}$$

$${K_p} < {K_c}$$

$${K_p} = {K_c}$$

$${K_p} = 1/{K_c}$$

## 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

$${K_p}$$ 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

$$C{H_3}CO{O^ - }$$ are added

$$C{H_3}COOH$$ 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

20

2

0.2

0.02

## Questions 11 of 50

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

$${H_2} + C{l_2}$$ $$\Leftrightarrow$$$$2HCl$$

$$2S{O_2} + {O_2}$$ $$\Leftrightarrow$$$$2S{O_3}$$

$${N_2} + {O_2}$$ $$\Leftrightarrow$$$$2NO$$

$$PC{l_5}$$ $$\Leftrightarrow$$$$PC{l_3} + C{l_2}$$

## Questions 12 of 50

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

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

$${K_P} = {P_{C{O_2}}}$$

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

$$\frac{{{K_p}[CaO][C{O_2}]}}{{[CaC{O_3}]}}$$

## 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

0.61

0.57

0.83

0.46

## 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 $${K_p}$$

Unchanged

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

7

20

49

21

## 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

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

4

27

4/27

1/27

## Questions 18 of 50

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

$$\frac{{[3A][2B]}}{C}$$

$$\frac{{[C]}}{{[3A][2B]}}$$

$$\frac{{{{[A]}^3}{{[B]}^2}}}{{[C]}}$$

$$\frac{{[C]}}{{{{[A]}^3}{{[B]}^2}}}$$

## 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

6.4

0.64

1.6

16

## 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

$$\frac{1}{4}$$

$$\frac{1}{2}$$

1

4

## 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

$$1 \times {10^{ - 2}}$$

$$2 \times {10^{ - 3}}$$

$$1 \times {10^{ - 5}}$$

$$2 \times {10^{ - 5}}$$

## Questions 22 of 50

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

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

$$mol\,\,litr{e^{ - 1}}$$

$$litre\,\,mo{l^{ - 1}}$$

$$mol\,\,litre$$

Dimensionless

## 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

0.1

1

10

$$\infty$$

## 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

0.3

0.18

0.17

0.11

## 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

0.073

0.147

0.05

0.026

## 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

5

10

15

20

## 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

4

2

$$1/4$$

$$1/2$$

## 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

30.66

32.66

34.66

36.66

## Questions 30 of 50

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

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

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

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

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

## 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

2.5

2

0.5

1.5

## Questions 32 of 50

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

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

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

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

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

## 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

$$4 \times {10^{ - 4}}$$

$$50$$

$$2.5 \times {10^2}$$

0.02

## Questions 34 of 50

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

$${K_c} = {[{O_2}]^5}$$

$${K_c} = [{P_4}{O_{10}}]/5[{P_4}][{O_2}]$$

$${K_c} = [{P_4}{O_{10}}]/[{P_4}]{[{O_2}]^5}$$

$${K_c} = 1/{[{O_2}]^5}$$

## 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, $${K_c}$$

20.2

25.4

0.284

11.1

## Questions 36 of 50

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

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

Atomic weight

Molecular weight

Equivalent weight

Active mass

## Questions 38 of 50

Question:Which is false

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

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 $${C_2}{H_6}$$

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

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

Decreases

Increases

Unaffected

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

$${N_2} + 3{H_2}$$ $$\Leftrightarrow$$ $$2N{H_3}$$

$${H_2} + {I_2}$$ $$\Leftrightarrow$$ $$2HI$$

$${H_2} + C{l_2}$$ $$\Leftrightarrow$$ $$2HCl$$

$${N_2}{O_4}$$ $$\Leftrightarrow$$ $$2NO$$

## Questions 44 of 50

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

$$2HI$$ $$\Leftrightarrow$$$${H_2} + {I_2}$$

$$2S{O_2} + {O_2}$$ $$\Leftrightarrow$$$$2S{O_3}$$

$${H_2} + B{r_2}$$ $$\Leftrightarrow$$$$2HBr$$

$${H_2}O + CO$$ $$\Leftrightarrow$$$${H_2} + C{O_2}$$

## Questions 45 of 50

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

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

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

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

Does not change

Forward

Backward

Decrease

## Questions 49 of 50

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

$$PC{l_3} + C{l_2}$$ $$\Leftrightarrow$$$$PC{l_5}$$

$${N_2} + 3{H_2}$$ $$\Leftrightarrow$$$$2N{H_3}$$

$${N_2} + {O_2}$$ $$\Leftrightarrow$$ 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