All questions of Chemical Equilibrium for Chemistry Exam

• A:

  16

• B:

  0.5

• C:

  2

• D:

  32

The answer is a.

• a)
  2SO₃ (g) ⇔ 2SO₂ (g) + O₂ (g)
• b)
  H₂ (g) + I₂ (s) ⇔ 2HI (g)
• c)
  C(s) + H₂O (g) ⇔ CO (g) + H₂ (g)
• d)
  3Fe(s) + 4H₂O (g) ⇔ Fe₃O₄ (s) + 4H₂ (g)

Ag⁺(aq)+NH₃(aq) [Ag(NH₃)(aq)]⁺ ; K, = 3.5x 10^-3
[Ag(NH₃)]⁺ (aq)+NH₃(aq) [Ag(NH₃)₂]²⁺(aq); K₂ = 1.7x 10^-3
Formation constant of [Ag(NH₃)₂]⁺(aq) is

• a)
  2.06
• b)
  5.2 x 10^-3
• c)
  5.95 x 10^-6
• d)
  None of these

For the reaction, the equilibrium constant K_p changes with:

• a)
  Total pressure
• b)
  Catalyst
• c)
  The amount of H₂ and I₂ Present
• d)
  Temperature

Q. What is [PCI₅] eq?

• a)
  4.09 x 10^-4 mol L^-1
• b)
  2.444 x 10³ mol L^-1 
• c)
  4.09 x 10^-6 mol L^-1
• d)
  2.444 x 10⁵ mol L^-1

Passage II

The complex ion of Fe²⁺ with the chelating agent dipyridyl (abbreviated dipy) has been studied kinetically in both the forward and backward directions. For the complexion reaction,

the rate of the formation of the complex at 298 K is given by rate = (1. 45 x 10¹³ L³mol ^-3s^-1) [Fe ²⁺] [dipy]³ and for the reverse reaction , the rate of disapperance of the complex is

Q. What is equilibrium constant for the equilibrium ? 

• a)
  8.4138x 10^-18
• b)
  2.3770x 10¹⁷
• c)
  1.1885x 10¹⁷
• d)
  5.9426x 10⁶

For the pair of reactions given below,

i)  

If at a particular temperature, K_p1 and K_p2 are the equilibrium constants for reaction (i) and (ii) respectively then,

• a)
  
• b)
  
• c)
  
• d)
  

• a)
  0.05
• b)
  50
• c)
  0.1
• d)
  25 RT

Consider the following gaseous equilibria given below

The equilibrium constant for the reaction, in terms of K₁, K₂ and K₃ will be

• a)
  K₁K₂K₃
• b)
  
• c)
  
• d)
  

• a)
  4.0 × 10^–6
• b)
  5.0 × 10^–6
• c)
  3.3 × 10^–7
• d)
  5.0 × 10^–7

 is a gaseous phase equilibrium reaction taking place at 400 K in a 5 L flask. For this 

• a)
  K_c = K_p
• b)
  K_c = 25Kp
• c)
  K_p = 25K_c
• d)
  K_c = 5K_p 

Does Le-Chatelier’s principle predict a change of equilibrium concentrations for the following reaction if the gas mixture is compressed:

• a)
  Yes, backward reaction is favoured                                 
• b)
  Yes, forward reaction is favoured           
• c)
  No change in equilibrium composition is predicted           
• d)
  No information is obtained about concentration changes

For the following gaseous phase equilibrium,

K_p is found to be equal to K_x (K_x is equilibrium constant when concentration are taken in terms of mole fraction. This is attained when pressure is 

• a)
  1 atm
• b)
  0.5 atm
• c)
  2 atm
• d)
  4 atm

9.2 grams of N₂O₄(g) is taken in a closed on litre vessel and heated till the following equilibrium is reached

At equilibrium, 50% N₂O₄(g) is dissociated. What is the equilibrium constant (in mol litre^–1) (molecular weight of N₂O₄ = 92)

• a)
  0.1 
• b)
  0.4                               
• c)
  0.2                               
• d)
  2

For the reaction:

At a given temperature, the equilibrium amount of CO₂(g) can be increased by.

• a)
  Adding a suitable catalyst
• b)
  Adding an inert gas
• c)
  Decreasing the volume of the container
• d)
  Increasing the amount of CO(g)

Direction (Q. Nos. 21) Choice the correct combination of elements and column I and coloumn II  are given as option (a), (b), (c) and (d), out of which ONE option is correct.

The progress of the reaction  with time t is shown below.


Match the parameters in Column l with their respective values in Column II.


Codes

      

• a)
  a
• b)
  b
• c)
  c
• d)
  d

For the chemical reaction,

The amount of X₃ Y at equilibrium is affected by

• a)
  Temperature and pressure
• b)
  Temperature only
• c)
  Pressure only
• d)
  Temperature, pressure and catalyst

Select the correct statement (s) about the following equilibrium.

• a)
  At constant vapour pressure, number of molecules leaving the liquid equals the number returning to liquid from vapour
• b)
  This does not represent the static equilibrium
• c)
  This represents dynamic equilibrium and the rate of the forward and backward reactions become equal
• d)
  This represents dynamic as well as static equilibrium

Then the formation constant of [Ag(NH₃)₂]⁺ is:

• a)
  6.08 × 10^–6
• b)
  6.08 × 10⁶
• c)
  6.08 × 10^–9
• d)
  None of these.

When a reversible reaction  is followed with time with initial concentration of A being 0.6 mol. L^–1, the following graph is obtained:

The equilibrium constant K, for the above reaction is:

• a)
  2 mol L^–1
• b)
  1.2 mol L^–1
• c)
  0.5 mol L^–1
• d)
  0.4 mol L^–1

• a)
  50 grams                     
• b)
  67 grams                     
• c)
  133 grams                   
• d)
  100 grams.

For the following equilibrium, N₂O₄ (g) 2NO₂(g)

K_p = K_C. This is attained when

• a)
  T = 1.0K
• b)
  T = 12.18 K
• c)
  T = 27.3 K
• d)
  T = 273 K

The concentration of the oxides of nitrogen are monitored in air-pollution reports. At 25°C, the equilibrium constant for the reaction,

 is 1.3 x 106 and that for 

is 6.5 x 10^-16 (when each species is expressed in terms of partial pressure).
For the reaction,

equilibrium constant is

• a)
  
• b)
  
• c)
  
• d)
  

• a)
  nRT
• b)
  1/RT
• c)
  (RT)²
• d)
  1/RT²

For the reaction,  the equilibrium constant K_p changes with:

• a)
  Total pressure                                                                    
• b)
  Catalyst                                 
• c)
  The amount of H₂ and I₂ present                          
• d)
  Temperature

For the reaction, 
if K_p = K_c (RT)^X, when the symbols have usual meaning, the value of x is (assuming ideality)

[jee Main 2014]

• a)
  -1
• b)
  -1/2
• c)
  +1/2
• d)
  +1

For the reaction in equilibrium, A B

Thus, K is

• a)
  
• b)
  
• c)
  
• d)
  

Pure ammonia is placed in a vessel at a temperature where its dissociation constant (α) is appreciable. At equilibrium,

• a)
  K_p does not change significantly with pressure.
• b)
  α Does not change with pressure.
• c)
  Concentration of NH₃ does not change with pressure.
• d)
  Concentration of hydrogen is less than that of nitrogen.

• a)
  Pb(NO₃)₂ (aq) + 2NaI (aq) = PbI₂(s) + 2NaNO₃(aq)
• b)
  AgNO₃(aq) + HCl(aq) = AgCl(s) + HNO₃(aq)
• c)
  2Na(s) + 2H₂O(l) = 2NaOH(aq) + H₂(g)
• d)
  KNO₃(aq) + NaCl(aq) = KCl(aq) + NaNO₃(aq)

• a)
  yes
• b)
  cannot say
• c)
  no
• d)
  depends on the temperature

• a)
   4.0
• b)
  0.4
• c)
  0.0001
• d)
  0.04

• a)
  Is zero
• b)
  Decreases with time
• c)
  Is independent of time
• d)
  Increases with time

• a)
  2.444 x 10^-3 
• b)
  4.09
• c)
  4.09 x 10²
• d)
  0.244 mol L^-1

If the equilibrium reaction  is heated, it is observed that the concentration of A increases. Then,

• a)
  A must be a gas
• b)
  Either B or C must be solid           
• c)
  The reaction is exothermic
• d)
  The reaction is endothermic

• a)
  homogeneous equilibrium
• b)
  not in both Homogeneous and heterogeneous equilibrium
• c)
  cannot say
• d)
  may or may not be in Homogeneous equilibrium

The equilibrium constant K_c for the following reaction at 842°C is 7.90 × 10^–3. What is K_p at same temperature:

• a)
  8.64 × 10^–5
• b)
  8.26 × 10^–4
• c)
  7.90 × 10^–2
• d)
  7.56 × 10^–2

Given that for the equilibrium constants of two reactions,

areK₁ and K₂. Equilibrium constant k₃ of the following reaction in terms of k₁, and K₂.

• a)
  K₁ K₂
• b)
  K₁ / K₂
• c)
  K₂ / K₁
• d)
  

• a)
  true
• b)
  flase

• a)
  homogeneous equilibrium
• b)
  heterogeneous equilibrium
• c)
  neither homogeneous nor heterogeneous
• d)
  both homogeneous and heterogeneous

• a)
  4 x 10^-3
• b)
  1 x 10^-3
• c)
  3 x 10^-3
• d)
  2 x 10^-3

Consider the following equilibrium in a closed container

At a fixed temperature, the volume of the reaction container is halved. For this change, which of the following statements hold true regarding the equilibrium constant (K_p) and degree of dissociation (α)?

• a)
  Neither nor change
• b)
  Both and change
• c)
  change but does not change
• d)
  does not change but change

• a)
  true
• b)
  false

• a)
  homogeneous chemical equilibrium
• b)
  heterogeneous chemical equilibrium
• c)
  neither homogeneous nor heterogeneous
• d)
  both homogeneous and heterogeneous

For the reaction: the equilibrium constant at 2000 K and 1.0 bar is 5.25. When the pressure is increased by 8-fold, the equilibrium constant:           

• a)
  Increases by a factor of 1.86                                
• b)
  Decreases by a factor of 1.86           
• c)
  Remains same                   
• d)
  Increases by factor of 8

• a)
  1.0                               
• b)
  2.0                               
• c)
  3.0                               
• d)
  4.0

For the reversible reaction, 
at 500° C, the value of K_p is 1.44x 10^-5, when partial pressure is measured in atmosphere. The corresponding value of K_c with concentration in mol L^-1 is

[IITJEE 2000]

• a)
  
• b)
  
• c)
  
• d)