Students of class 11 Chemistry should refer to MCQ Questions Class 11 Chemistry Equilibrium with answers provided here which is an important chapter in Class 11 Chemistry NCERT textbook. These MCQ for Class 11 Chemistry with Answers have been prepared based on the latest CBSE and NCERT syllabus and examination guidelines for Class 11 Chemistry. The following MCQs can help you to practice and get better marks in the upcoming class 11 Chemistry examination

Chapter 7 Equilibrium MCQ with Answers Class 11 Chemistry

MCQ Questions Class 11 Chemistry Equilibrium provided below have been prepared by expert teachers of grade 11. These objective questions with solutions are expected to come in the upcoming Standard 11 examinations. Learn the below provided MCQ questions to get better marks in examinations.

Question. For the following equilibrium,N₂O₄ 2NO₂
s in gaseous
phase, NO₂ is 50% of the total volume when equilibrium
is set up. Hence, per cent of dissociation of N₂ O₄ is
(a) 50%
(b) 25%
(c) 66.66%
(d) 33.33%

Question. At certain temperature and a total pressure of 10⁵ Pa  , iodine vapours contains 40% by volume of iodine atoms. K_p for the equilibriumI₂ (g) ⇔ 2I (g) will be
(a) 0.67
(b)1.5
(c) 2.67×10⁴

Question. In the given reaction,
     2X (g) + Y (g) ⇔ Z (g) + 80 kcal
which combination of pressure and temperature
gives the highest yield of Z at equilibrium?
(a) 1000 atm and 500°C
(b) 500 atm and 500°C
(c) 1000 atm and 100°C
(d) 500 atm and 100°C

Question. In a chemical reaction, the rate constant for the backward reaction is 7.5 ×10^–4 and the equilibrium constant is 1.5. The rate constant for the forward reaction is
(a) 5 × 10 ^–4
(b) 2 × 10 ^–3
(c) 1.125 × 10⁻³
(d) 9.0 × 10 ^–4

Question. 56 g of N₂ and 6 g of H₂ were kept at 400°C in 1 L vessel. The equilibrium mixture contained 27.54 g of NH₃. The approximate value of K_C for the above reaction inmol^{– 2} L² is
(a) 0.128
(b) 0.118
(c) 0.148
(d) 0.008

Question. The concentration of CO² which will be in equilibrium with 2.5 ×10^–2 mol L^–1 of CO at 100°C. For the reaction
FeO(s) + CO(g)⇔ Fe (s) + CO₂ (g);KC= 5.0 will be
(a) 0.5 × 10^–1 mol L^–1
(b) 1.25 × 10^–1 mol L^–1
(c) 2 × 10^–2 mol L^–1
(d) None of these

Question. 1.1 moles of A are mixed with 2.2 moles of B and the mixture is kept in a 1 L flask till the equilibrium,
A + 2B s 2C + D is reached. At equilibrium, 0.2 mole of C is formed. The equilibrium constant of the above reaction is
(a) 0.0002
(b) 0.004
(c) 0.001
(d) 0.003

Question. In aqueous solution, the ionisation constants for carbonic acid are K₁ = 4.2 × 10⁻⁷ and K₂ = 4.8 × 10⁻¹¹
Select the correct statement for a saturated 0.034 M solution of the carbonic acid. 
(a) The concentration of CO₃²⁻ is 0.034 M
(b) The concentration of CO₃²⁻ is greater than that ofHCO₃⁻
(c) The concentration ofH⁺ andHCO₃⁻ are approximately equal
(d) The concentration ofH⁺ is double that of CO₂⁻

Question. For the reaction,
          2NO₂(g) ⇔ 2NO(g) + O₂(g)
[K_C = 1.8 ×10⁻⁶ at 184°C, R = 0.00831 kJ/(mol K)]
when K_p and K_C are compared at 184°C it is found that
(a) whether K_p is greater than, less than or equal toK_C depends upon the total gas pressure
(b) K_p = KC 
(c) K_p is less than K_C
(d) K_p is greater than K_C

Question. For the reaction,
       SO₂  (g) + 1/2 O₂(g)⇔ SO₃(g)
i fK_p K_C (RT)^x where, the symbols have their usual meaning then the value of x is (assuming ideality) 
(a) −1
(b) − 1/2
(c) 1/2
(d) 1

Question. The ratio K_p/K_C for the reaction,
CO(g) + 1/2O₂(g) ⇔ CO₂(g)s is
(a) 1/√ RT
(b) (RT)  1/2
(c) RT
(d) 1

Question. A reversible chemical reaction is having two reactants in equilibrium. If the concentration of the reactants are doubled then the equilibrium constant will
(a) be doubled
(b) become one fourth
(c) be halved
(d) remain the same

Question. For the following three reactions (I), (II) and (III), equilibrium constants are given
I. CO(g) + H₂O(g) ⇔ CO₂(g) +H₂(g);K₁
II. CH₄(g) + H₂O(g) ⇔ CO(g) +3H₂(g);K₂
III. CH₄(g)+₂H₂O(g) ⇔ CO₂(g)+4H₂(g); K₃
Which of the following relation is correct?
(a) K₃ = K₁ K₂
(b) K₃ K³₂ = K²₁
(c) K₁ √K₂ = K₃
(d) K₂ K₃ = K₁

Question. 8 For the reaction,
CO(g) + Cl₂(g) s COCl₂(g), the K_p/K_C is equal to
(a) 1/RT
(b) RT
(c) √RT
(d) 1.0

Question. For the following reaction in gaseous phase
CO + 1/2 O₂ → CO₂.K_C/K_p is
(a) (RT)1/2
(b) (RT)^−1/2
(c) (RT)
(d) (RT)−¹

Question. 17 An aqueous solution contains 0.10 MH2S  and 0.20 M HCl. If the equilibrium constants for the formation of HS− fromH2S is10 × 10⁻⁷.  and that of S²⁻ from HS− ions is 12 × 10⁻¹³ . then the concentration of S²⁻ ions in aqueous solution is
(a) 5 × 10⁻⁸
(b) 3 × 10^–20
(c) 6 × 10^–21
(d) 5 × 10^–19

Question. 56 g of N₂ and 6 g of H₂ were kept at 400°C in 1 L vessel. The equilibrium mixture contained 27.54 g of NH₃. The approximate value of K_C for the above reaction inmol^{– 2} L² is
(a) 0.128
(b) 0.118
(c) 0.148
(d) 0.008

Question. The concentration of CO² which will be in equilibrium with 2.5 ×10^–2 mol L^–1 of CO at 100°C. For the reaction.
 (s) + CO(g)⇔ Fe (s) + CO₂ (g);KC= 5.0 will be
(a) 0.5 × 10^–1 mol L^–1
(b) 1.25 × 10^–1 mol L^–1
(c) 2 × 10^–2 mol L^–1
(d) None of these

Question. The equilibrium constant (K_C)  for the reaction
N₂(g) + O₂(g) ⇔ 2 NO (g)at temperatureT is 4 × 10⁻⁴. The value of K_C for the reaction.
NO (g) ⇔ 1/2 N₂ (g) + 1/2 O₂ (g)at the same temperature is
(a) 0.02
(b) 2.5 ×10 2
(c) 4 ×10−4
(d) 50.0

Question. For the following equilibrium,N O 2NO 2 4 2
s in gaseous
phase, NO2 is 50% of the total volume when equilibrium
is set up. Hence, per cent of dissociation of N O 2 4 is
(a) 50%
(b) 25%
(c) 66.66%
(d) 33.33%

Question. At certain temperature and a total pressure of 10⁵ Pa  , iodine vapours contains 40% by volume of iodine atoms. K_p for the equilibriumI₂ (g) ⇔ 2I (g) will be
(a) 0.67
(b)1.5
(c) 2.67×10⁴
(d) 9.0 ×104

Question. Which molecule is an electron donor?
(a) NH₃
(b) BF₃
(c) PF₅
(d) AsF₅   

Question. How much is the pH of human blood? 
(a) 5.2
(b) 8.3
(c) 6.3
(d) 7.4         

Question. The concentration of hydrogen ion in a sample of soft drink is 3.8 x 10^-3 M. What is its pH? 
(a) 3.84
(b) 2.42
(c) 4.44
(d) 1.42       

Question. How many litres of water must be added to 1 L of an aqueous solution of HCI with a pH of 1 to create an aqueous solution with pH of 2 ? 
(a) 0.1 L
(b) 0.9L
(c) 2.0 L
(d) 9.0 L       

Question. By adding 20 mL of0. l N HCI to 20 mL of 0.001 N KOH, the pH of the obtained solution will be 
(a) 2
(b) 1.3
(c) 0
(d) 7           

Question. hich of these is a Lewis acid?
(a) AICI₃
(b) NCI₃
(c) HCI
(d) ROR       

Question. What will be the pH of a solution formed by mixing 10 mL N of 0.1 M H₂SO₄ and 10 mL of N/10  KOH?
(a) 11.40
(b) 8.64
(c) 1.00
(d) 7.00     

Question. A monoprotic acid in 1.00 M solution is 0.01 % ionised. The dissociation constant of this acid is 
(a) 1 x 10^-8
(b) 1 x 10^-4
(c) 1 x 10^-6
(d) 1 x 10^-5     

Question. The pH of a 0.1 molar solution of the acid HQ is 3. The value of the ionisation constant, K_a of the acid is
(a) 3 X 10^-1
(b) 1 X 10^-3 
(c) 1x 10^-5
(d) 1 x 10^-7           

Question. If K_a of HCN= 4 x 10^-10 , then the pH of 2.5 x 10^-1 molar HCN ( aq) is
(a) 1
(c) 4
(b) 2.5
(d) 5   

Question. On adding which of the following, the pH of 20 mL of 0.1 N HCl will not alter? 
(a) 20 mL of distilled water
(b) 1 mL of 0.1 N NaOH
(c) 500 mL of HCl of pH = 1
(d) I mL of I NHCI       

Question. 5 mL of0.4 N NaOH is mixed with 20 mL of 0.1 N HCI. The pH of the resulting solution will be 
(a) 7
(b) 8
(c) 5
(d) 6       

Question. The pH of the solution obtained by mixing 100 mL of a solution of pH = 3 with 400 mL of a solution of pH = 4, is
(a) 7 – log 2.8
(b) 4 – log 2.8 
(c) 5 – log 2.8
(d) 3 – log 2.8       

Question. Which of the following is not a Lewis base ?
(a) NH₃
(b) H₂O
(c) AICI₃
(d) None of these       

Question. The pH of 10^-4 M KOH solution will be
(a) 4
(b) 11
(c) 10.5
(d) 10     

Question.  In the given reaction,
     2X (g) + Y (g) ⇔ Z (g) + 80 kcal
which combination of pressure and temperature
gives the highest yield of Z at equilibrium?
(a) 1000 atm and 500°C
(b) 500 atm and 500°C
(c) 1000 atm and 100°C
(d) 500 atm and 100°C

Question.  A vessel at 1000 K contains CO₂ with a pressure of 0.5 atm. Some of the CO₂ is converted into CO on the addition of graphite. If the total pressure at equilibrium is 0.8 atm, the value of K_p is 
(a) 1.8 atm
(b) 3 atm
(c) 0.3 atm
(d) 0.18 atm

Question.  Ammonium carbamate decomposes as
        NH₂COONH₄ (s) ⇔ 2NH₃ (g) + CO₂ (g) 
For this reaction, Kp = 2.9 ×10^–5 atm³. If we start with
1 mole of the compound, the total pressure at equilibrium
would be
(a) 0.0766 atm
(b) 0.0581 atm
(c) 0.0388 atm
(d) 0.0194 atm

Question. In reaction A + 2B s 2C + D, initial concentration of B was 1.5 times of [A], but at equilibrium the concentrations
of A and B became equal. The equilibrium constant for the reaction is
(a) 8
(b) 4
(c) 12
(d) 6

Question.  In the given reaction,
     2X (g) + Y (g) ⇔ Z (g) + 80 kcal
which combination of pressure and temperature
gives the highest yield of Z at equilibrium?
(a) 1000 atm and 500°C
(b) 500 atm and 500°C
(c) 1000 atm and 100°C
(d) 500 atm and 100°C

Question.  The following reactions are known to occur in the body
      CO₂ + H₂O → H₂CO₃ ⇔ H⁺ + HCO₃⁻
If CO₂ escapes from the system
(a) pH will decreases
(b) hydrogen ion concentration will diminish
(c) H₂CO₃ concentration will be altered
(d) the forward reaction will be promoted

Question. Consider the reaction equilibrium,
    2SO₂(g) + O₂ (g)⇔ 2SO₃(g); ΔH° = –198 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 of temperature as well as pressure
(c) lowering the temperature and increasing the pressure
(d) any value of temperature and pressure

Question. 1 Formaldehyde polymerises to form glucose according to the reaction, 6HCHO ⇔  C₆ H₁₂O₆ The theoretically computed equilibrium constant for this reaction is found to be 6 ×10²². If 1M solution of glucose dissociates according to the above equilibrium, the concentration of formaldehyde in the solution will be
(a) 1.6 × 10^–2 M  
(b) 1.6 × 10^–4 M 
(c) 1.6 × 10^–6 M 
(d) 1.6 × 10^–8 M 

Question. Consider the following equilibrium in a closed container
       N₂O₄(g) ⇔ 2NO₂(g)
At a fixed temperature, the volume of the reaction container is halved. For this change, which of the following statements holds true regarding the equilibrium constant Kp and degree of dissociation (a)?
(a) Neither Kp nor a changes
(b) Both Kp and a changes
(c) Kp changes but a does not
(d) Kp does not change but a change

Question. For the reaction, N₂O₄(g)s 2NO₂ (g) the degree of dissociation at equilibrium is 0.2 at 1 atm pressure. The
equilibrium constant, K_p will be
(a) 1/2
(b) 1/4
(c) 1/6
(d) 1/8

Question..23 At 30°C, Kp for the dissociation reaction
      SO₂Cl₂(g) ⇔ SO₂(g)+ Cl₂
is 2.9 ×  10^–2 atm. If the total pressure is 1 atm, the degree of dissociation of SO₂Cl₂ is (assume, 1– a² =1)
(a) 87%
(b) 13%
(c) 17%
(d) 29%

Question.The equilibrium constant for the reaction,
H₂(g)+ I₂ (g) ⇔ 2HI(g) is 64. If the volume of the container is reduced to half of the original volume, the value of the equilibrium constant will be
(a) 16
(b) 32
(c) 64
(d) 128

36 The exothermic formation ofClF₃ (g) is represented by the equation,
     Cl₂(g)+ 3F₂(g) ⇔ 2ClF₃(g) ; Δr = –329 kJ
Which of the following will increase the quantity ofClF₃ in an equilibrium mixture of Cl₂,F₂ and ClF₃?
(a) Adding F₂
(b) Increasing the volume of the container
(c) Removing Cl₂
(d) Increasing the temperature

Question.Starting with one mole ofO₂ and two moles of SO₂, the equilibrium for the formation of SO₃ was established at a certain temperature. If V is the volume of the vessel and 2 x is the number of moles of SO  present, the equilibrium constant will be
(a) x²V/(1–x)³
(b) 4x²(/2 – x)(1 – x)
(c) (1–x)3/2^V
(d) x²/(2 – )(1–x)

Question.Volume of the flask in which species are transferred is double of the earlier flask. In which of the following
cases, equilibrium constant is affected?
I. N₂(g) + 3H₂(g)⇔2NH₃(g)
II. N₂(g) +O₂(g) ⇔ 2NO(g)
III. PCl₅(g) ⇔ PCl₃(g) + Cl₂(g)
IV. 2NO(g) ⇔ N₂(g) +O₂(g)
(a) Both I and II
(b) Both II and III
(c) Both I and III
(d) Both III and IV

Question.Reaction between nitrogen and oxygen takes place as following
        2N₂(g) + O₂(g) ⇔ 2N₂O (g)
If a mixture of 0.482 mole of N2 and 0.933 mole ofO₂ is placed in a reaction vessel of volume 10 L and allowed to form N₂O  at a temperature for which K_C = 2.0 × 10⁻³⁷, the equilibrium concentration of [N₂O] will be
(a) 7.06 × 10 ⁻²⁰ mol L⁻¹
(b) 6.58 × 10⁻²¹ mol L⁻¹
(c) 4.82 × 10⁻⁴ mol L⁻¹
(d) 9.36 × 10⁻⁷ mol L⁻¹

Question. 4 moles of PCl₅ are heated in a closed 4dm³ container to reach equilibrium at 400 K. At equilibrium, 50% of PCl₅ is dissociated. What is the value of K_c for the dissociation of PCl₅ into PCl₃ and Cl₂ at 400 K?
(a) 0.50
(b) 1.00
(c) 1.15
(d) 0.05   

Question. Consider the following gaseous equilibria with equilibrium constants K₁ and K₂ , respectively.
       SO₂ (g) + 1/2 O₂(g) ⇌ SO₃(g)
                      2SO₃(g) ⇌ 2SO₂(g) + O₂(g)
The equilibrium constants are related as 
(a) 2K₁ = K²₂
(b) K^₁2 = 1/K₂
(c) K²₂ = 1/K₁
(d) K₂ = 2/K²₁     

Question. Final pressure is higher than initial pressure of a container filled with an ideal gas at constant temperature. What will be the value of equilibrium constant? 
(a) K = 1.0
(b) K = 10.0
(c) K > 1.0
(d) K < 1.0     

Question. In aqueous solution, the ionisation constants for carbonic acid are
      K₁ = 4.2 x 10^-7 and K₂ = 4.8 x 10^-11
Select the correct statement for a saturated 0.034 M solution of the carbonic acid. 
(a) The concentration of CO^2-₃ is 0.034 M
(b) The concentration of CO^2-₃ is greater than that of HCO^–₃
(c) The concentration of H⁺ and HCO^–₃ are approximately equal
(d) The concentration of H⁺ is double that of CO^2-₃     

Question. NH₄HS(s) ⇌ NH₃ (g) + H₂S(g)
In the above reaction, if the pressure at equilibrium and at 300 K is 100 atrn, then what will be the equilibrium constant K_P ? 
(a) 2500 atm²
(b) 50 atm²
(c) 100 atm²
(d) 200 atm²     

Question. 4NH₃ + 5O₂ ⇌ 4NO+ 6H₂O
For the homogeneous reaction, the equilibrium constant K_c has the units 
(a) cone. ⁺¹⁰
(b) conc.⁺¹
(c) cone. ^-1
(d) it is dimensionless     

Question. A reversible chemical reaction is having two reactants in equilibrium. If the concentration of the reactants are doubled, then the equilibrium constant will 
(a) be doubled
(b) become one-fourth
(c) be halved
(d) remain the same     

    

Question. For which one of the following reactions K_P = K_c ?
(a) PCl₅ ⇌ PCl₃ + Cl₂
(b) N₂ + O₂ ⇌ 2NO
(c) N2 + 3H₂ ⇌ 2NH₃
(d) 2SO₃ ⇌ 2SO₂ + O₂       

Question. 5 moles of SO₂ and 5 moles of O₂ are allowed to react. At equilibrium, it was found that 60% of SO₂ is used up. If the total pressure of the equilibrium mixture is 1 atrn, the pa1tial pressure of O₂ is 
(a) 0.82atm
(b) 0.52atm
(c) 0.2 l atm
(d) 0.4latm       

Question. 2HI(g) ⇌ H2 (g)+I₂(g)
The equilibrium constant of the above reaction is 6.4 at 300 K. If 0.25 mole each of H₂ and I₂ are added to the system at same temperature, then the equilibrium constant will be 
(a) 6.4
(b) 0.8
(c) 3.2
(d) 1.6     

Question. For PCl₅ ⇌ PCl₃ + Cl₂ , initial concentration of each reactant and product is I M. If K_eq  = 0· 4 1 then 
(a) more PCl₃ will fom,
(b) more Cl₂ will form
(c) more PCl₅ will fom,
(d) no change       

Question. Which of the following is not a physical equilibrium?
(a) Ice ⇌ Water 
(b) I₂ (s) ⇌ I2 (g)
(c) S(/) ⇌ S(g)
(d) 3O₂ ⇌ 2O₃       

Question. For an equilibrium reaction, if the value of K_c >> 1, then the reaction favoured more towards 
(a) backward
(b) forward
(c) equilibrium will be obtained
(d) reaction will stop   

Question. If the value of K_c for an equilibrium reaction is 10^-4, then the reaction is in 
(a) backward direction
(b) forward direction
(c) equilibrium
(d) reaction is not possible       

Question. For a reaction at equilibrium, which of the following is correct? 
(a) Concentration ofreactant = Concentration of product
(b) Concentration ofreactant is always greater than that of product
(c) Rate of forward reaction = Rate of backward reaction
(d) Q_c = k       

Question. Which of the following is a wrong statement about equilibrium state?
(a) Rate of forward reaction = Rate of backward reaction
(b) Equilibrium is dynamic
(c) Catalysts increase the value of equilibrium constant
(d) Free energy change is zero     

Question. A+B ⇌ C+D
in the above reaction, initially moles of A and Bare equal. At equilibrium, moles of C are three times that of A. The equilibrium constant of the reaction will be 
(a) 1
(b) 3
(c) 4
(d) 9       

Question.The values of Kp1 and Kp2 for the reactions,
       X ⇔  Y + Z      …(i)
      A ⇔  2B           …(ii)
are in the ratio of 9 : 1. If degree of dissociation of X and A be equal, then total pressure at equilibrium of reactions (I) and (II) are in the ratio.
(a) 3 : 1
(b) 1 : 9
(c) 36 : 1
(d) 1 : 1

Question.The equilibrium constant at 298K for a reaction,
A + B ⇔ C + D is 100. If the initial concentrations of all the four species were 1M each, then equilibrium concentration ofD (in mol L ⁻¹) will be
(a) 0.818
(b) 1.818
(c) 1.182
(d) 0.182

Question .On increasing the pressure, in which direction will the gas phase reaction proceed to re-establish equilibrium,
is predicted by applying the Le-Chatelier’s principle. Consider the reaction,
           N₂(g) + 3H₂(g) ⇔ 2NH₃(g)
Which of the following is correct, if the total pressure at which the equilibrium is established, is increased without
changing the temperature?
(a) K will remain same
(b) K will decrease
(c) K will increase
(d) K will increase initially and decrease when pressure is very high

Question .At 600°C, Kp for the following reaction is 1atm,
       X(g) ⇔ Y(g) + Z(g)
at equilibrium, 50%, of X(g) is dissociated. The total pressure of the equilibrium system is p atm. What is the
partial pressure (in atm) of X(g) at equilibrium?
(a) 1
(b) 4
(c) 2
(d) 0.5

Question. N₂ and H₂ in 1 : 3 molar ratio are heated in a closed container having a catalyst. When the following equilibrium, N₂(g) + 3H₂(g)⇔2NH₃(g) is attained, the total pressure is 10 atm and mole fraction ofNH₃ is 0.60. The equilibrium constant K_p for dissociation of NH₃ is
(a) 1.333 atm⁻²
(b) 0.75 atm²
(c) 0.75 atm⁻²
(d) 1.333 atm²

Question. The rate of the elementary reaction,
H₂(g) + I₂(g) → 2HI (g) at 25°C is given by
                  rate = 1.7 × 10⁻¹⁸ [H₂] [I₂] 
The rate of decomposition of gaseous HI toH₂ (g) and I₂(g) at 25°C is rate = 2.4× 10⁻²¹ [HI]². Equilibrium
constant for the formation of one mole of gaseous HI from the H₂(g) and I₂ (g) is
(a) 708
(b) 354
(c) 0.0014
(d) 26.6

Question. For N₂ + 3H₂ ⇔ 2NH₃ 1 mole of N₂ and 3 moles of H₂ are at 4 atm. Equilibrium pressure is found to be 3 atm. Hence, K_p is
(a) 1/(0.5) (0.15)³
(b) 1/(0.5) (1.5)³
(c) 3 x 3/(0.5) (0.5)3×
(d) None of these

Question. At 77°C and one atmospheric pressure,N₂O₄ is 70% dissociated into NO₂. What will be the volume occupied by the mixture under these conditions if we start with 10g of N₂O₄?
(a) 6.32 L
(b) 5.32 L
(c) 6.38 L
(d) 5.38 L

Question. In the reaction, AB(g)⇔A(g) + B(g) at 30°C, K_p for the dissociation pressure at equilibrium is 2.56 10 ×⁻² atm. If the total equilibrium is 1 atm, then the percentage dissociation of AB is
(a) 43.5%
(b) 13%
(c) 87%
(d) 16%

Question. When NH3 is heated in a 0.50 L flask at 700 K and 100 atm pressure, it decomposes into N₂ and H₂ and their equilibrium moles are given below:
2NH₃(g)⇔ N₂(g) + 3H₂(g)
0.30        0.30      0.90
Which of the pairs given represents correct value?
Initial moles of NH₃     K_C for NH₃ formation
(a) 0.80                       9.72
(b) 0.90                       9.72
(c) 0.80.                      1.03
(d) 0.90                       0.103

Question. The equilibrium constant Kp for the reaction,
      PCl₅ ⇔ PCl₃ Cl₂ + is 1.6 at 200°C.
The pressure at which PCl₅ will be 50% dissociated at 200°C is
(a) 3.2 atm
(b) 4.8 atm
(c) 2.4 atm
(d) 6.4 atm

Question. XY₂ dissociates as XY₂(g)s XY(g) +Y(g).
When the initial pressure of XY₂ is 600 mm Hg, the total equilibrium pressure is 800 mm Hg. Calculate K for the
reaction assuming that the volume of the system remains unchanged.
(a) 50
(b) 100
(c) 166.6
(d) 400.0

Question. On increasing the pressure, in which direction will the gas phase reaction proceed to re-establish equilibrium,
is predicted by applying the Le-Chatelier’s principle. Consider the reaction,
           N₂(g) + 3H₂(g) ⇔ 2NH₃(g)
Which of the following is correct, if the total pressure at which the equilibrium is established, is increased without
changing the temperature?
(a) K will remain same
(b) K will decrease
(c) K will increase
(d) K will increase initially and decrease when pressure is very high

We hope the above multiple choice questions for Class 11 Chemistry for Chapter 7 Equilibrium provided above with answers based on the latest syllabus and examination guidelines issued by CBSE, NCERT and KVS are really useful for you. Equilibrium is an important chapter in Class 11 as it provides very strong understanding about this topic. Students should go through the answers provided for the MCQs after they have themselves solved the questions. All MCQs have been provided with four options for the students to solve. These questions are really useful for the benefits of class 11 students. Please go through these and let us know if you have any feedback in the comments section.