11242 + Mcqs in Chemistry Page 86 McqOptions

4251.	The equilibrium constant (Kc) for the reaction \[\text{HA}+\text{B}\]⇌\[\text{B}{{\text{H}}^{+}}+{{\text{A}}^{-}}\] is 100. If the rate constant for the forward reaction is 105, then rate constant for the backward reaction is [CBSE PMT 2002]
A.	\[{{10}^{7}}\]
B.	\[{{10}^{3}}\]
C.	\[{{10}^{-3}}\]
D.	\[{{10}^{-5}}\]
Answer» C. \[{{10}^{-3}}\]

Discussion

4252.	The rate of forward reaction is two times that of reverse reaction at a given temperature and identical concentration. Kequilibrium is [KCET 2002]
A.	2.5
B.	2.0
C.	0.5
D.	1.5
Answer» C. 0.5

Discussion

4253.	In which of the following, the reaction proceeds towards completion [MNR 1990]
A.	\[K={{10}^{3}}\]
B.	\[K={{10}^{-2}}\]
C.	\[K=10\]
D.	\[K=1\]
Answer» B. \[K={{10}^{-2}}\]

Discussion

4254.	Change in volume of the system does not alter the number of moles in which of the following equilibrium [AIEEE 2002]
A.	\[{{N}_{2(g)}}+{{O}_{2(g)}}\]⇌ \[2N{{O}_{(g)}}\]
B.	\[PC{{l}_{5(g)}}\]⇌\[PC{{l}_{3(g)}}+C{{l}_{2(g)}}\]
C.	\[{{N}_{2(g)}}+3{{H}_{2}}_{(g)}\]⇌\[2N{{H}_{3(g)}}\]
D.	\[S{{O}_{2}}C{{l}_{2(g)}}\]⇌ \[S{{O}_{2(g)}}+C{{l}_{2(g)}}\]
Answer» B. \[PC{{l}_{5(g)}}\]⇌\[PC{{l}_{3(g)}}+C{{l}_{2(g)}}\]

Discussion

4255.	In a chemical reaction equilibrium is established when [MP PET 2001]
A.	Opposing reaction ceases
B.	Concentration of reactants and products are equal
C.	Velocity of opposing reaction is the same as that of forward reaction
D.	Reaction ceases to generate heat
Answer» D. Reaction ceases to generate heat

Discussion

4256.	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 [BHU 2000; CBSE PMT 2001]
A.	30.66
B.	32.66
C.	34.66
D.	36.66
Answer» C. 34.66

Discussion

4257.	15 moles of \[{{H}_{2}}\] and 5.2 moles of \[{{I}_{2}}\] are mixed and allowed to attain equilibrium at \[{{500}^{o}}C\]. At equilibrium, the concentration of \[HI\] is found to be 10 moles. The equilbrium constant for the formation of \[HI\] is [KCET 2005]
A.	50
B.	15
C.	100
D.	25
Answer» B. 15

Discussion

4258.	In the reaction, \[A+B\]⇌\[2C\], at equilibrium, the concentration of A and B is \[0.20\,\,mol\,\,{{l}^{-1}}\] each and that of C was found to be \[0.60\,\,mol\,\,{{l}^{-1}}\]. The equilibrium constant of the reaction is [MH CET 2000]
A.	2.4
B.	18
C.	4.8
D.	9
Answer» E.

Discussion

4259.	For the equilibrium \[{{N}_{2}}+3{{H}_{2}}\]⇌\[2N{{H}_{3}},{{K}_{c}}\] at 1000K is \[2.37\times {{10}^{-3}}\]. If at equilibrium \[[{{N}_{2}}]=2M,\,[{{H}_{2}}]=3M\], the concentration of \[N{{H}_{3}}\] is [JIPMER 2000]
A.	0.00358 M
B.	0.0358 M
C.	0.358 M
D.	3.58 M
Answer» D. 3.58 M

Discussion

4260.	Equilibrium concentration of \[HI,\,{{I}_{2}}\] and \[{{H}_{2}}\] is \[0.7,\,0.1\] and \[0.1\,M\] respectively. The equilibrium constant for the reaction \[{{I}_{2}}+{{H}_{2}}\]⇌\[2HI\] is [JIPMER 2000]
A.	36
B.	49
C.	0.49
D.	0.36
Answer» C. 0.49

Discussion

4261.	A 1 M solution of glucose reaches dissociation equilibrium according to equation given below \[6HCHO\]⇌\[{{C}_{6}}{{H}_{12}}{{O}_{6}}\]. What is the concentration of HCHO at equilibrium if equilibrium constant is \[6\times {{10}^{22}}\] [MP PMT 2000]
A.	\[1.6\times {{10}^{-8}}M\]
B.	\[3.2\times {{10}^{-6}}M\]
C.	\[3.2\times {{10}^{-4}}M\]
D.	\[1.6\times {{10}^{-4}}M\]
Answer» E.

Discussion

4262.	When 3 mole of A and 1 mole of B are mixed in 1 litre vessel the following reaction takes place \[{{A}_{(g)}}+{{B}_{(g)}}\]⇌\[2{{C}_{(g)}}\]. 1.5 moles of C are formed. The equilibrium constant for the reaction is [MP PMT 2000]
A.	0.12
B.	0.25
C.	0.50
D.	4.0
Answer» E.

Discussion

4263.	At a certain temp. 2HI ⇌ H2 + I2 Only 50% HI is dissociated at equilibrium. The equilibrium constant is [DCE 1999]
A.	0.25
B.	1.0
C.	3.0
D.	0.50
Answer» B. 1.0

Discussion

4264.	On a given condition, the equilibrium concentration of \[HI,\,{{H}_{2}}\] and \[{{I}_{2}}\] are 0.80, 0.10 and 0.10 mole/litre. The equilibrium constant for the reaction \[{{H}_{2}}+{{I}_{2}}\] ⇌ \[2HI\] will be [MP PET 1986]
A.	64
B.	12
C.	8
D.	0.8
Answer» B. 12

Discussion

4265.	The rate constant for forward and backward reactions of hydrolysis of ester are \[1.1\times {{10}^{-2}}\] and \[1.5\times {{10}^{-3}}\] per minute respectively. Equilibrium constant for the reaction is \[C{{H}_{3}}COO{{C}_{2}}{{H}_{5}}+{{H}_{2}}O\]⇌\[C{{H}_{3}}COOH\]\[+{{C}_{2}}{{H}_{5}}OH\] [AIIMS 1999]
A.	4.33
B.	5.33
C.	6.33
D.	7.33
Answer» E.

Discussion

4266.	At 3000 K the equilibrium pressures of CO2, CO and O2 are 0.6,0.4 and 0.2 atmospheres respectively. \[{{K}_{p}}\]for the reaction, \[2C{{O}_{2}}\]⇌\[2CO+{{O}_{2}}\] is [JIPMER 1999]
A.	0.089
B.	0.0533
C.	0.133
D.	0.177
Answer» B. 0.0533

Discussion

4267.	An equilibrium mixture of the reaction \[2{{H}_{2}}S(g)\]⇌\[2{{H}_{2}}(g)+{{S}_{2}}(g)\] had 0.5 mole \[{{H}_{2}}S\], 0.10 mole \[{{H}_{2}}\] and 0.4 mole \[{{S}_{2}}\] in one litre vessel. The value of equilibrium constant \[(K)\] in mole litre-1 is [AIIMS 1998; IIT 1992; AFMC 1999; UPSEAT 2001]
A.	0.004
B.	0.008
C.	0.016
D.	0.160
Answer» D. 0.160

Discussion

4268.	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 [BHU 1998; KCET 2000]
A.	4
B.	2
C.	\[1/4\]
D.	\[1/2\]
Answer» B. 2

Discussion

4269.	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 \[CO+C{{l}_{2}}\] ⇌\[COC{{l}_{2}}\] is [CBSE PMT 1998]
A.	5
B.	10
C.	15
D.	20
Answer» C. 15

Discussion

4270.	In the reaction \[A+2B\]⇌\[2C\], 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 [KCET 1996]
A.	0.073
B.	0.147
C.	0.05
D.	0.026
Answer» D. 0.026

Discussion

4271.	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 [AIEEE 2005]
A.	0.30
B.	0.18
C.	0.17
D.	0.11
Answer» E.

Discussion

4272.	The equilibrium concentration of \[X,\,Y\] and \[Y{{X}_{2}}\] are 4, 2 and 2 moles respectively for the equilibrium \[2X+Y\]⇌\[Y{{X}_{2}}\]. The value of \[{{K}_{c}}\] is [EAMCET 1990]
A.	0.625
B.	0.0625
C.	6.25
D.	0.00625
Answer» C. 6.25

Discussion

4273.	28 g of \[{{N}_{2}}\] and 6 g of \[{{H}_{2}}\] were kept at \[{{400}^{o}}C\] in 1 litre vessel, the equilibrium mixture contained \[27.54g\] of \[N{{H}_{3}}\]. The approximate value of \[{{K}_{c}}\] for the above reaction can be (in \[mol{{e}^{-2}}\,\,litr{{e}^{2}}\]) [CBSE PMT 1990]
A.	75
B.	50
C.	25
D.	100
Answer» B. 50

Discussion

4274.	4 moles of A are mixed with 4 moles of B. At equilibrium for the reaction \[A+B\]⇌\[C+D\], 2 moles of C and D are formed. The equilibrium constant for the reaction will be [CPMT 1992]
A.	\[\frac{1}{4}\]
B.	\[\frac{1}{2}\]
C.	1
D.	4
Answer» D. 4

Discussion

4275.	In a chemical equilibrium, the rate constant of the backward reaction is \[7.5\times {{10}^{-4}}\] and the equilibrium constant is 1.5. So the rate constant of the forward reaction is [KCET 1989]
A.	\[5\times {{10}^{-4}}\]
B.	\[2\times {{10}^{-3}}\]
C.	\[1.125\times {{10}^{-3}}\]
D.	\[9.0\times {{10}^{-4}}\]
Answer» D. \[9.0\times {{10}^{-4}}\]

Discussion

4276.	A mixture of 0.3 mole of \[{{H}_{2}}\] and 0.3 mole of \[{{I}_{2}}\] is allowed to react in a 10 litre evacuated flask at \[{{500}^{o}}C\]. The reaction is \[{{H}_{2}}+{{I}_{2}}\]⇌ \[2HI\], the \[K\] is found to be 64. The amount of unreacted \[{{I}_{2}}\] at equilibrium is [KCET 1990]
A.	0.15 mole
B.	0.06 mole
C.	0.03 mole
D.	0.2 mole
Answer» C. 0.03 mole

Discussion

4277.	A quantity of \[PC{{l}_{5}}\] was heated in a 10 litre vessel at \[{{250}^{o}}C\]; \[PC{{l}_{5}}(g)\]⇌ \[PC{{l}_{3}}(g)+C{{l}_{2}}(g)\]. At equilibrium the vessel contains 0.1 mole of \[PC{{l}_{5}}\,0.20\] mole of \[PC{{l}_{3}}\] and 0.2 mole of \[C{{l}_{2}}\]. The equilibrium constant of the reaction is [KCET 1993, 2001; MP PMT 2003]
A.	0.02
B.	0.05
C.	0.04
D.	0.025
Answer» D. 0.025

Discussion

4278.	For the reaction \[2S{{O}_{2}}+{{O}_{2}}\] ⇌ \[2S{{O}_{3}}\], the units of \[{{K}_{c}}\] are [CPMT 1990]
A.	\[litre\,mol{{e}^{-1}}\]
B.	\[mol\,\,litr{{e}^{-1}}\]
C.	\[{{(mol\,\,litr{{e}^{-1}})}^{2}}\]
D.	\[{{(litre\,\,mol{{e}^{-1}})}^{2}}\]
Answer» B. \[mol\,\,litr{{e}^{-1}}\]

Discussion

4279.	In the gas phase reaction, \[{{C}_{2}}{{H}_{4}}+{{H}_{2}}\]⇌ \[{{C}_{2}}{{H}_{6}}\], the equilibrium constant can be expressed in units of [CBSE PMT 1992; Pb. PMT 1999]
A.	\[litr{{e}^{-1}}\,mol{{e}^{-1}}\]
B.	\[litre\,mol{{e}^{-1}}\]
C.	\[mol{{e}^{2}}\,litr{{e}^{-2}}\]
D.	\[mole\,litr{{e}^{-1}}\]
Answer» C. \[mol{{e}^{2}}\,litr{{e}^{-2}}\]

Discussion

4280.	If in the reaction \[{{N}_{2}}{{O}_{4}}=2N{{O}_{2}},\,\alpha \] is that part of \[{{N}_{2}}{{O}_{4}}\] which dissociates, then the number of moles at equilibrium will be [MP PET 1990; MH CET 2001; KCET 2005]
A.	3
B.	1
C.	\[{{(1-\alpha )}^{2}}\]
D.	\[(1+\alpha )\]
Answer» E.

Discussion

4281.	The suitable expression for the equilibrium constant of the reaction \[2N{{O}_{(g)}}+C{{l}_{2(g)}}\] ⇌ \[2NOC{{l}_{(g)}}\] is [CPMT 1983, 87]
A.	\[{{K}_{c}}=\frac{[2NOCl]}{[2NO]\,[C{{l}_{2}}]}\]
B.	\[{{K}_{c}}=\frac{{{[NOCl]}^{2}}}{{{[NO]}^{2}}[C{{l}_{2}}]}\]
C.	\[{{K}_{c}}=\frac{{{[NOCl]}^{2}}}{[NO]{{[C{{l}_{2}}]}^{2}}}\]
D.	\[{{K}_{c}}=\frac{{{[NOCl]}^{2}}}{{{[NO]}^{2}}{{[C{{l}_{2}}]}^{2}}}\]
Answer» C. \[{{K}_{c}}=\frac{{{[NOCl]}^{2}}}{[NO]{{[C{{l}_{2}}]}^{2}}}\]

Discussion

4282.	For the reaction \[{{N}_{2(g)}}+3{{H}_{2(g)}}\] ⇌ \[2N{{H}_{3(g)}}\], the correct expression of equilibrium constant K is [CPMT 1984, 2000]
A.	\[K=\frac{{{[N{{H}_{3}}]}^{2}}}{[{{N}_{2}}]{{[{{H}_{2}}]}^{3}}}\]
B.	\[K=\frac{[{{N}_{2}}]{{[{{H}_{2}}]}^{3}}}{{{[N{{H}_{3}}]}^{2}}}\]
C.	\[K=\frac{2[N{{H}_{3}}]}{[{{N}_{2}}]\times 3[{{H}_{2}}]}\]
D.	\[K=\frac{[{{N}_{2}}]\times 3[{{H}_{2}}]}{2[N{{H}_{3}}]}\]
Answer» B. \[K=\frac{[{{N}_{2}}]{{[{{H}_{2}}]}^{3}}}{{{[N{{H}_{3}}]}^{2}}}\]

Discussion

4283.	In a chemical equilibrium \[A+B\] ⇌ \[C+D\], when one mole each of the two reactants are mixed, 0.6 mole each of the products are formed. The equilibrium constant calculated is [CBSE PMT 1989]
A.	1
B.	0.36
C.	2.25
D.	4/9
Answer» D. 4/9

Discussion

4284.	In the reversible reaction \[A+B\]⇌ \[C+D\], the concentration of each C and D at equilibrium was 0.8 mole/liter, then the equilibrium constant \[{{K}_{c}}\] will be [MP PET 1986]
A.	6.4
B.	0.64
C.	1.6
D.	16.0
Answer» E.

Discussion

4285.	The unit of equilibrium constant K for the reaction \[A+B\]⇌ \[C\] would be [CPMT 1987]
A.	\[mol\,\,litr{{e}^{-1}}\]
B.	\[litre\,\,mo{{l}^{-1}}\]
C.	\[mol\,\,litre\]
D.	Dimensionless
Answer» C. \[mol\,\,litre\]

Discussion

4286.	In a reaction \[A+B\]⇌ \[C+D\], 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 [BHU 1981]
A.	0.1
B.	1.0
C.	10
D.	\[\infty \]
Answer» C. 10

Discussion

4287.	Concentration of a gas is expressed in the following terms in the calculation of equilibrium constant [EAMCET 1982]
A.	No. of molecules per litre
B.	No. of grams per litre
C.	No. of gram equivalent per litre
D.	No. of molecules equivalent per litre
Answer» B. No. of grams per litre

Discussion

4288.	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 \[{{N}_{2}}{{O}_{4}}\] ⇌ \[2N{{O}_{2}}\] is [AIIMS 1984]
A.	\[1\times {{10}^{-2}}\]
B.	\[2\times {{10}^{-3}}\]
C.	\[1\times {{10}^{-5}}\]
D.	\[2\times {{10}^{-5}}\]
Answer» D. \[2\times {{10}^{-5}}\]

Discussion

4289.	Unit of equilibrium constant for the reversible reaction \[{{H}_{2}}+{{I}_{2}}\] ⇌ \[2HI\] is [DPMT 1984]
A.	\[mo{{l}^{-1}}\,litre\]
B.	\[mo{{l}^{-2}}\,litre\]
C.	\[mol\,\,litr{{e}^{-1}}\]
D.	None of these
Answer» E.

Discussion

4290.	For which of the following reactions does the equilibrium constant depend on the units of concentration [AIIMS 1983]
A.	\[N{{O}_{(g)}}\] ⇌ \[\frac{1}{2}{{N}_{2(g)}}+\frac{1}{2}{{O}_{2(g)}}\]
B.	\[Z{{n}_{(s)}}+Cu_{(aq)}^{2+}\] ⇌ \[C{{u}_{(s)}}+Zn_{(aq)}^{2+}\]
C.	\[{{C}_{2}}{{H}_{5}}O{{H}_{(l)}}+C{{H}_{3}}COO{{H}_{(l)}}\]⇌\[C{{H}_{3}}COO{{C}_{2}}{{H}_{5(l)}}+{{H}_{2}}{{O}_{(l)}}\] (Reaction carried in an inert solvent)
D.	\[COC{{l}_{2(g)}}\] ⇌ \[C{{O}_{(g)}}+C{{l}_{2\,(g)}}\]
Answer» E.

Discussion

4291.	2 moles of \[PC{{l}_{5}}\] were heated in a closed vessel of 2 litre capacity. At equilibrium, 40% of \[PC{{l}_{5}}\] is dissociated into \[PC{{l}_{3}}\] and \[C{{l}_{2}}\]. The value of equilibrium constant is [MP PMT 1989; RPMT 2000; UPSEAT 2004; Kerala CET 2005]
A.	0.266
B.	0.53
C.	2.66
D.	5.3
Answer» B. 0.53

Discussion

4292.	For the reaction \[A+2B\] ⇌ \[C\], the expression for equilibrium constant is [MNR 1987; MP PMT 1999; UPSEAT 2002]
A.	\[\frac{[A]{{[B]}^{2}}}{[C]}\]
B.	\[\frac{[A][B]}{[C]}\]
C.	\[\frac{[C]}{[A]{{[B]}^{2}}}\]
D.	\[\frac{[C]}{2[B][A]}\]
Answer» D. \[\frac{[C]}{2[B][A]}\]

Discussion

4293.	Partial pressures of A, B, C and D on the basis of gaseous system \[A+2B\] ⇌ \[C+3D\] are A = 0.20; B = 0.10; C = 0.30 and D = 0.50 atm. The numerical value of equilibrium constant is [CPMT 1987]
A.	11.25
B.	18.75
C.	5
D.	3.75
Answer» C. 5

Discussion

4294.	For the system \[3A+2B\] ⇌ \[C\], the expression for equilibrium constant is [NCERT 1981; CPMT 1989; MP PMT 1990; RPMT 1999; Pb. PMT 2002; Pb. CET 2002]
A.	\[\frac{[3A][2B]}{C}\]
B.	\[\frac{[C]}{[3A][2B]}\]
C.	\[\frac{{{[A]}^{3}}{{[B]}^{2}}}{[C]}\]
D.	\[\frac{[C]}{{{[A]}^{3}}{{[B]}^{2}}}\]
Answer» E.

Discussion

4295.	In the reaction \[{{N}_{2}}(g)+3{{H}_{2}}\] ⇌ \[2N{{H}_{3}}(g)\], the value of the equilibrium constant depends on [CPMT 1990; AIIMS 1991; MP PET 1996]
A.	Volume of the reaction vessel
B.	Total pressure of the system
C.	The initial concentration of nitrogen and hydrogen
D.	The temperature
Answer» E.

Discussion

4296.	\[N{{H}_{4}}COON{{H}_{2(s)}}\] ⇌ \[2N{{H}_{3(g)}}+C{{O}_{2(g)}}\] if equilibrium pressure is 3 atm for the above reaction \[{{K}_{p}}\] for the reaction is [DPMT 2005]
A.	4
B.	27
C.	4/27
D.	1/27
Answer» C. 4/27

Discussion

4297.	\[{{A}_{(g)}}+3{{B}_{(g)}}\] ⇌\[4{{C}_{(g)}}\]. Starting concentration of A is equal to B, equilibrium concentration of A and C are same. \[{{K}_{c}}=\] [Kerala CET 2005]
A.	0.08
B.	0.8
C.	8
D.	80
E.	1/8
Answer» D. 80

Discussion

4298.	For the reaction \[{{N}_{2(g)}}+{{O}_{2(g)}}\] ⇌\[2N{{O}_{(g)}}\], the value of \[{{K}_{c}}\] at \[{{800}^{o}}C\] is 0.1. When the equilibrium concentrations of both the reactants is 0.5 mol, what is the value of \[{{K}_{p}}\] at the same temperature [KCET 2005]
A.	0.5
B.	0.1
C.	0.01
D.	0.025
Answer» C. 0.01

Discussion

4299.	If equilibrium constants of reaction, \[{{N}_{2}}+{{O}_{2}}\]⇌ \[2NO\] is \[{{K}_{1}}\]and \[\]\[\frac{1}{2}{{N}_{2}}+\frac{1}{2}{{O}_{2}}\]⇌ \[NO\] is \[{{K}_{2}}\], then [BHU 2004]
A.	\[{{K}_{1}}={{K}_{2}}\]
B.	\[{{K}_{2}}=\sqrt{{{K}_{1}}}\]
C.	\[{{K}_{1}}=2{{K}_{2}}\]
D.	\[{{K}_{1}}=\frac{1}{2}{{K}_{2}}\]
Answer» C. \[{{K}_{1}}=2{{K}_{2}}\]

Discussion

4300.	What is the effect of increasing pressure on the dissociation of \[PC{{l}_{5}}\] according to the equation \[PC{{l}_{5(g)}}\]⇌ \[PC{{l}_{3(g)}}+C{{l}_{2(g)}}-x\ cal\] [UPSEAT 2004]
A.	Dissociation decreases
B.	Dissociation increases
C.	Dissociation does not change
D.	None of these
Answer» B. Dissociation increases

Discussion

Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

The equilibrium constant (Kc) for the reaction \[\text{HA}+\text{B}\]⇌\[\text{B}{{\text{H}}^{+}}+{{\text{A}}^{-}}\] is 100. If the rate constant for the forward reaction is 105, then rate constant for the backward reaction is [CBSE PMT 2002]

The rate of forward reaction is two times that of reverse reaction at a given temperature and identical concentration. Kequilibrium is [KCET 2002]

In which of the following, the reaction proceeds towards completion [MNR 1990]

Change in volume of the system does not alter the number of moles in which of the following equilibrium [AIEEE 2002]

In a chemical reaction equilibrium is established when [MP PET 2001]

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 [BHU 2000; CBSE PMT 2001]

15 moles of \[{{H}_{2}}\] and 5.2 moles of \[{{I}_{2}}\] are mixed and allowed to attain equilibrium at \[{{500}^{o}}C\]. At equilibrium, the concentration of \[HI\] is found to be 10 moles. The equilbrium constant for the formation of \[HI\] is [KCET 2005]

In the reaction, \[A+B\]⇌\[2C\], at equilibrium, the concentration of A and B is \[0.20\,\,mol\,\,{{l}^{-1}}\] each and that of C was found to be \[0.60\,\,mol\,\,{{l}^{-1}}\]. The equilibrium constant of the reaction is [MH CET 2000]

For the equilibrium \[{{N}_{2}}+3{{H}_{2}}\]⇌\[2N{{H}_{3}},{{K}_{c}}\] at 1000K is \[2.37\times {{10}^{-3}}\]. If at equilibrium \[[{{N}_{2}}]=2M,\,[{{H}_{2}}]=3M\], the concentration of \[N{{H}_{3}}\] is [JIPMER 2000]

Equilibrium concentration of \[HI,\,{{I}_{2}}\] and \[{{H}_{2}}\] is \[0.7,\,0.1\] and \[0.1\,M\] respectively. The equilibrium constant for the reaction \[{{I}_{2}}+{{H}_{2}}\]⇌\[2HI\] is [JIPMER 2000]

A 1 M solution of glucose reaches dissociation equilibrium according to equation given below \[6HCHO\]⇌\[{{C}_{6}}{{H}_{12}}{{O}_{6}}\]. What is the concentration of HCHO at equilibrium if equilibrium constant is \[6\times {{10}^{22}}\] [MP PMT 2000]

When 3 mole of A and 1 mole of B are mixed in 1 litre vessel the following reaction takes place \[{{A}_{(g)}}+{{B}_{(g)}}\]⇌\[2{{C}_{(g)}}\]. 1.5 moles of C are formed. The equilibrium constant for the reaction is [MP PMT 2000]

At a certain temp. 2HI ⇌ H2 + I2 Only 50% HI is dissociated at equilibrium. The equilibrium constant is [DCE 1999]

On a given condition, the equilibrium concentration of \[HI,\,{{H}_{2}}\] and \[{{I}_{2}}\] are 0.80, 0.10 and 0.10 mole/litre. The equilibrium constant for the reaction \[{{H}_{2}}+{{I}_{2}}\] ⇌ \[2HI\] will be [MP PET 1986]

At 3000 K the equilibrium pressures of CO2, CO and O2 are 0.6,0.4 and 0.2 atmospheres respectively. \[{{K}_{p}}\]for the reaction, \[2C{{O}_{2}}\]⇌\[2CO+{{O}_{2}}\] is [JIPMER 1999]

An equilibrium mixture of the reaction \[2{{H}_{2}}S(g)\]⇌\[2{{H}_{2}}(g)+{{S}_{2}}(g)\] had 0.5 mole \[{{H}_{2}}S\], 0.10 mole \[{{H}_{2}}\] and 0.4 mole \[{{S}_{2}}\] in one litre vessel. The value of equilibrium constant \[(K)\] in mole litre-1 is [AIIMS 1998; IIT 1992; AFMC 1999; UPSEAT 2001]

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 [BHU 1998; KCET 2000]

In the reaction \[A+2B\]⇌\[2C\], 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 [KCET 1996]

The equilibrium concentration of \[X,\,Y\] and \[Y{{X}_{2}}\] are 4, 2 and 2 moles respectively for the equilibrium \[2X+Y\]⇌\[Y{{X}_{2}}\]. The value of \[{{K}_{c}}\] is [EAMCET 1990]

28 g of \[{{N}_{2}}\] and 6 g of \[{{H}_{2}}\] were kept at \[{{400}^{o}}C\] in 1 litre vessel, the equilibrium mixture contained \[27.54g\] of \[N{{H}_{3}}\]. The approximate value of \[{{K}_{c}}\] for the above reaction can be (in \[mol{{e}^{-2}}\,\,litr{{e}^{2}}\]) [CBSE PMT 1990]

4 moles of A are mixed with 4 moles of B. At equilibrium for the reaction \[A+B\]⇌\[C+D\], 2 moles of C and D are formed. The equilibrium constant for the reaction will be [CPMT 1992]

In a chemical equilibrium, the rate constant of the backward reaction is \[7.5\times {{10}^{-4}}\] and the equilibrium constant is 1.5. So the rate constant of the forward reaction is [KCET 1989]

A mixture of 0.3 mole of \[{{H}_{2}}\] and 0.3 mole of \[{{I}_{2}}\] is allowed to react in a 10 litre evacuated flask at \[{{500}^{o}}C\]. The reaction is \[{{H}_{2}}+{{I}_{2}}\]⇌ \[2HI\], the \[K\] is found to be 64. The amount of unreacted \[{{I}_{2}}\] at equilibrium is [KCET 1990]

For the reaction \[2S{{O}_{2}}+{{O}_{2}}\] ⇌ \[2S{{O}_{3}}\], the units of \[{{K}_{c}}\] are [CPMT 1990]

In the gas phase reaction, \[{{C}_{2}}{{H}_{4}}+{{H}_{2}}\]⇌ \[{{C}_{2}}{{H}_{6}}\], the equilibrium constant can be expressed in units of [CBSE PMT 1992; Pb. PMT 1999]

If in the reaction \[{{N}_{2}}{{O}_{4}}=2N{{O}_{2}},\,\alpha \] is that part of \[{{N}_{2}}{{O}_{4}}\] which dissociates, then the number of moles at equilibrium will be [MP PET 1990; MH CET 2001; KCET 2005]

The suitable expression for the equilibrium constant of the reaction \[2N{{O}_{(g)}}+C{{l}_{2(g)}}\] ⇌ \[2NOC{{l}_{(g)}}\] is [CPMT 1983, 87]

For the reaction \[{{N}_{2(g)}}+3{{H}_{2(g)}}\] ⇌ \[2N{{H}_{3(g)}}\], the correct expression of equilibrium constant K is [CPMT 1984, 2000]

In a chemical equilibrium \[A+B\] ⇌ \[C+D\], when one mole each of the two reactants are mixed, 0.6 mole each of the products are formed. The equilibrium constant calculated is [CBSE PMT 1989]

In the reversible reaction \[A+B\]⇌ \[C+D\], the concentration of each C and D at equilibrium was 0.8 mole/liter, then the equilibrium constant \[{{K}_{c}}\] will be [MP PET 1986]

The unit of equilibrium constant K for the reaction \[A+B\]⇌ \[C\] would be [CPMT 1987]

In a reaction \[A+B\]⇌ \[C+D\], 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 [BHU 1981]

Concentration of a gas is expressed in the following terms in the calculation of equilibrium constant [EAMCET 1982]

Unit of equilibrium constant for the reversible reaction \[{{H}_{2}}+{{I}_{2}}\] ⇌ \[2HI\] is [DPMT 1984]

For which of the following reactions does the equilibrium constant depend on the units of concentration [AIIMS 1983]

2 moles of \[PC{{l}_{5}}\] were heated in a closed vessel of 2 litre capacity. At equilibrium, 40% of \[PC{{l}_{5}}\] is dissociated into \[PC{{l}_{3}}\] and \[C{{l}_{2}}\]. The value of equilibrium constant is [MP PMT 1989; RPMT 2000; UPSEAT 2004; Kerala CET 2005]

For the reaction \[A+2B\] ⇌ \[C\], the expression for equilibrium constant is [MNR 1987; MP PMT 1999; UPSEAT 2002]

Partial pressures of A, B, C and D on the basis of gaseous system \[A+2B\] ⇌ \[C+3D\] are A = 0.20; B = 0.10; C = 0.30 and D = 0.50 atm. The numerical value of equilibrium constant is [CPMT 1987]

For the system \[3A+2B\] ⇌ \[C\], the expression for equilibrium constant is [NCERT 1981; CPMT 1989; MP PMT 1990; RPMT 1999; Pb. PMT 2002; Pb. CET 2002]

In the reaction \[{{N}_{2}}(g)+3{{H}_{2}}\] ⇌ \[2N{{H}_{3}}(g)\], the value of the equilibrium constant depends on [CPMT 1990; AIIMS 1991; MP PET 1996]

\[N{{H}_{4}}COON{{H}_{2(s)}}\] ⇌ \[2N{{H}_{3(g)}}+C{{O}_{2(g)}}\] if equilibrium pressure is 3 atm for the above reaction \[{{K}_{p}}\] for the reaction is [DPMT 2005]

\[{{A}_{(g)}}+3{{B}_{(g)}}\] ⇌\[4{{C}_{(g)}}\]. Starting concentration of A is equal to B, equilibrium concentration of A and C are same. \[{{K}_{c}}=\] [Kerala CET 2005]

For the reaction \[{{N}_{2(g)}}+{{O}_{2(g)}}\] ⇌\[2N{{O}_{(g)}}\], the value of \[{{K}_{c}}\] at \[{{800}^{o}}C\] is 0.1. When the equilibrium concentrations of both the reactants is 0.5 mol, what is the value of \[{{K}_{p}}\] at the same temperature [KCET 2005]

If equilibrium constants of reaction, \[{{N}_{2}}+{{O}_{2}}\]⇌ \[2NO\] is \[{{K}_{1}}\]and \[\]\[\frac{1}{2}{{N}_{2}}+\frac{1}{2}{{O}_{2}}\]⇌ \[NO\] is \[{{K}_{2}}\], then [BHU 2004]

What is the effect of increasing pressure on the dissociation of \[PC{{l}_{5}}\] according to the equation \[PC{{l}_{5(g)}}\]⇌ \[PC{{l}_{3(g)}}+C{{l}_{2(g)}}-x\ cal\] [UPSEAT 2004]