NEET Chemistry Equilibrium MCQs Set B

Question:  At 30°C, the solubility of Ag₂CO₃(Ksp= 8 × 10^–12) would be maximum in 1 litre of

• a) 0.05 M Na₂CO₃
• b) 0.05 M AgNO₃
• c) Pure water
• d) 0.05 M NH₃

Answer:  0.05 M NH₃

Question:  For the reaction,

Equilibrium constant Kc= 2 Degree of association is

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which of the following solutions will have pH close to 1?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Silver nitrate is gradually added to an aqueous solution containing 0.01 M each of chloride, bromide and iodide ions. The correct sequence (decreasing order) in which the halides will be precipitated is

• a) Br^–, Cl^–, I^– 
• b) I^–, Cl^–, Br^–
• c) I^–, Br^–, Cl^– 
• d) Cl^–, Br^–, I^–

Answer:  I^–, Br^–, Cl^– 

Question: When a small amount of HCl is added to a buffer solution of acetic acid and sodium acetate

• a) pH Increases
• b) [H⁺] decreases
• c) Dissociation of acetic acid decreases
• d) [CH₃COO^–_] increases

Answer: Dissociation of acetic acid decreases

Question: When equal volumes of pH = 4 and pH = 6 are mixed together then the pH of the resulting solution will be[log 5 = 0.7]

• a) 4.3
• b) 4.7
• c) 5
• d) 5.3

Answer: 4.3

Question: Which causes the change in the value of equilibrium constant of any equilibria?

• a) Adding of inert gas at constant pressure
• b) Increasing the pressure
• c) Adding of inert gas at constant volume
• d) Decreasing the temperature

Answer: Decreasing the temperature

Question:  The pH of 10^–11 M HCl at 25°C is

• a) 11
• b) 3
• c) Slightly greater than 7
• d) Slightly less than 7

Answer: Slightly less than 7

Question:  If ionic product of water is K_w= 10^–16 at 4°C, then a solution with pH = 7.5 at 4°C will

• a) Turn blue litmus red
• b) Turn red litmus blue
• c) Be neutral to litmus
• d) Be alkaline

Answer: Turn blue litmus red

Question: The value of K_p for the reaction,

What will be the partial pressure of O₂ at equilibrium when equal moles of SO₂ and SO₃ are present at equilibrium?

• a) 0.5
• b) 0.3
• c) 0.2
• d) 0.1

Answer: 0.2

Question:  The solubility product of AgBr is 4.9 × 10^–9. The solubility of AgBr will be

• a) 7 × 10^–4 mole/litre
• b) 7 × 10^–5 g/litre
• c) 1.316 × 10^–2 g/litre
• d) 1 × 10^–3 mole/litre

Answer: 1.316 × 10^–2 g/litre

Question: In which of the following solution, AgCl has minimum solubility?

• a) 0.05 M AgNO₃ 
• b) 0.01 M CaCl₂
• c) 0.01 M NaCl 
• d) 0.01 M NH₄OH

Answer:  0.05 M AgNO₃ 

Question: Le-chatelier's principle is not applicable to

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: A solution of NaOH contain 0.04 gm of NaOH per litre. Its pH is

• a) 10
• b) 9
• c) 11
• d) 12

Answer: 11

Question: 1 c.c of 0.1 N HCl is added to 1 litre solution of sodium chloride. The pH of the resulting solution will be

• a) 7
• b) 0
• c) 10
• d) 4

Answer: 4

Question:  The pH of

is

• a) 1.699
• b) 12
• c) 12.301
• d) 12.699

Answer: 12.301

Question: 100 c.c. of N/10 NaOH solution is mixed with 100 c.c. of N/5 HCl solution and the whole volume is made to 1 litre. The pH of the resulting solution will be

• a) 1
• b) 2
• c) 3
• d) 4

Answer: 2

Question:   The pH of a mixture of 100 ml 1M H₂SO₄ and 200 ml 1N NaOH at 25°C is

• a) More than 7
• b) Less than 7
• c) Equal to 7
• d) Can’t predict

Answer: Equal to 7

Question:  The solubility product of BaSO₄ is 4 × 10^–10. The solubility of BaSO₄ in presence of 0.02 N H₂SO₄ will be

• a) 4 × 10^–8 M 
• b) 2 × 10^–8 M
• c) 2 × 10^–5 M 
• d) 2 × 10^–4 M

Answer:  4 × 10^–8 M 

Question:    The pH of a mixture of 0.01M HCl and 0.1M CH₃COOH is approximately

• a) 1
• b) 2
• c) 4
• d) 7

Answer: 2

More Questions.................................

Question:  The equilibrium constants for  at 400 K and 600 K are 1 × 10^–8 and 1 × 10^–2 respectively. The reaction is

• a) Exothermic
• b) Endothermic
• c) May be exothermic or endothermic
• d) No heat is evolved or absorbed

Answer: Endothermic

Question:  Two samples of CH₃COOH each of 10 g were taken separately in two vessels containing water of 6 litre and 12 litre respectively at 27°C. The degree of dissociation of CH₃COOH will be

• a) More in 12 litre vessel
• b) More in 6 litre vessel
• c) Equal in both vessels
• d) Half in 6 litre vessel than in 12 litre vessel

Answer: More in 12 litre vessel

Question:  Following three gaseous equilibrium reactions are occurring at 27°C

• a) A < C < B
• b) A < B < C
• c) C < B < A
• d) B < C < A

Answer: A < C < B

Question:  Solubility product of the salt, A_xB_y will be represented most suitably, if the solubility is represented by S

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which is incorrect?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: A buffer solution can be obtained from

• a) HCN and KCN
• b) CH₃COONH₄ 
• c) NH₄Cl and NH₄OH 
• d) All of these

Answer:  CH₃COONH₄ 

Question: Which of the following statements is correct for a reversible process in a state of equilibrium?

• a) ΔG° = 2.30 RT log K 
• b) ΔG = –2.30 RT log K
• c) ΔG = 2.30 RT log K
• d) ΔG° = –2.30 RT log K

Answer:  ΔG° = –2.30 RT log K

Question:  If the value of an equilibrium constant for a particular reaction is 1.6 × 10¹², then at equilibrium the system will contain 

• a) Similar amounts of reactants and products
• b) All reactants
• c) Mostly reactants
• d) Mostly products

Answer: Mostly products

Question: Which of the folowing salts will give highest pH in water?

• a) KCl
• b) NaCl
• c) Na₂CO₃
• d) CuSO₄

Answer:  Na₂CO₃

Question:   The K_sp  of Ag₂CrO₄ , AgCl, AgBr and AgI are respectively, 1.1 × 10^–12, 1.8 × 10^–10, 5.0 × 10^–13, 8.3 × 10^–17. Which one of the following salts will precipitate last if AgNO₃ solution is added to the solution containing equal moles of NaCl, NaBr, NaI and Na₂CrO₄ ? 

• a) Ag₂CrO₄
• b) AgI
• c) AgCl
• d) AgBr

Answer:   Ag₂CrO₄ 

Question:  For a given exothermic reaction, K_p and K’_p are the equilibrium constants at temperatures T₁ and T₂ , respectively. Assuming that heat of reaction is constant in temperature range between T₁ and T₂ , it is readily observed that

• a) K_p and K’_p
• b) K_p< K’_p 
• c) K_p= K’_p
• d)

  

Answer:  K_p and K’_p

Question:  For the reversible re action

The equilibrium shifts in forward direction

• a) By increasing the concentration of NH₃(g)
• b) By decreasing the pressure
• c) By decreasing the concentrations of N₂(g) and H₂(g)
• d) By increasing pressure and decreasing temperature

Answer: By increasing pressure and decreasing temperature

Question: Identify the correct order of solubility in aqueous medium

• a) ZnS > Na₂S > CuS
• b) Na₂S > CuS > ZnS
• c) Na₂S > ZnS > CuS
• d) CuS > ZnS > Na₂S

Answer:  Na₂S > ZnS > CuS

Question:  KMnO₄ can be prepared from K₂MnO₄ as per the reaction,

The reaction can go to completion by removing OH^– ions by adding 

• a) KOH
• b) CO₂  
• c) SO₂
• d) HCl

Answer: CO₂  

Question:  Using the Gibbs energy change, ΔG°= +63.3 kJ, for the following reaction,

the K_sp of Ag₂CO₃(s) in water at 25°C is(R = 8.314 J K^–1 mol^–1) 

• a) 3.2 × 10^–26
• b) 8.0 × 10^–12
• c) 2.9 × 10^–3 
• d) 7.9 × 10^–2

Answer:  8.0 × 10^–12

Question: Buffer solutions have constant acidity and alkalinity because

• a) They have large excess of H⁺ or OH^– ions
• b) They have fixed value of pH
• c) These give unionised acid or base on reaction with added acid or alkali
• d) Acids and alkalies in these solutions are shielded from attack by other ions

Answer: These give unionised acid or base on reaction with added acid or alkali

Question:  pH of a saturated solution of Ba(OH)₂ is 12. The value of solubility product (K_sp) of Ba(OH)₂ is

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

Answer:  5.0×10^–7

Question:  Given that the equilibrium constant for the reaction

has a value of 278 at a particular temperature. What is the value of the equilibirum constant for the following reaction at the same temperature ?

• a) 1.8 × 10^–3 
• b) 3.6 × 10^–3 
• c) 6.0 × 10^–2 
• d) 1.3 × 10^–5

Answer:  6.0 × 10^–2 

Question:  Given the reaction between 2 gases represented by A₂ and B₂ to give the compound AB(g).

At equilibrium, the concentration

of A₂= 3.0 × 10^–3 M

of B₂= 4.2 × 10^–3 M

of AB = 2.8 × 10^–3 M

If the reaction takes place in a sealed vessel at 527°C, then the value of K_c will be 

• a) 2.0
• b) 1.9
• c) 0.62
• d) 4.5

Answer: 0.62

Question:  A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of NH₄⁺ is 0.20M. If the equilibrium constant, K_b for NH₃ equals 1.8 × 10^–5, what is the pH of this solution? (log 2.7 = 0.43)

• a) 8.73
• b) 9.08
• c) 9.43
• d) 11.72

Answer: 9.43

Question:  For the reaction,

the equilibrium constant is K₁ . The equilibrium constant is K₂ for the reaction

What is K for the reaction

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:    In qualitative analysis, the metals of group I can be separated from other ions by precipitating them as chloride salts. A solution initially contains Ag⁺ and Pb²⁺ at a concentration is 0.10 M. Aqueous HCl is added to this solution until the Cl^– concentration is 0.10 M. What will the concentration of Ag⁺ and Pb²⁺ be at equilibrium?

(K_sp for AgCl = 1.8×10^–10, K_sp for PbCl₂= 1.7×10^–5)

• a)

  [Ag⁺] = 1.8 × 10^–9 M 

  [Pb²⁺] = 1.7 × 10^–3 M   

• b)

  [Ag⁺] = 1.8 × 10^–11 M

  [Pb²⁺] = 1.7 × 10^–4 M

• c)

  [Ag⁺] = 1.8 × 10^–6 M     

  [Pb²⁺] = 1.7 × 10^–11 M    

• d)

  [Ag⁺] = 1.8 × 10^–11 M

  [Pb²⁺] = 8.5 × 10^–5 M

Answer:

[Ag⁺] = 1.8 × 10^–9 M 

[Pb²⁺] = 1.7 × 10^–3 M   

Question:  The value of ΔH for the reaction

is less than zero. Formation of XY₄(g) will be favoured at: 

• a) High pressure and low temperature
• b) High tremperature and high pressure
• c) Low pressure and low temperature
• d) High temperature and low pressure

Answer: High pressure and low temperature

Question:  In which of the following equilibrium K_c and K_p are not equal?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:  What is [H⁺] in mol/L of a solution that is 0.20 M  CH₃COONa and 0.10 M in CH₃COOH ? (K_a for CH₃COOH = 1.8×10^–5) 

• a) 3.5 × 10^–4
• b) 1.1 × 10^–5
• c) 1.8 × 10^–5
• d) 9.0 × 10^–6

Answer:  9.0 × 10^–6

Question:  In a buffer solution containing equal concentration of B^– and HB, the K_b for B^– is 10^–10. The pH of buffer solution is 

• a) 10
• b) 7
• c) 6
• d) 4

Answer: 4

Question:   The reaction,

is begun with the concentrations of A and B both at an initial value of 1.00 M. When equilibrium is reached,the concentration of D is measured and found to be 0.25 M. The value for the equilibrium constant for this reaction is given by the expression 

• a) [(0.75)³(0.25)] ÷ [(1.00)²(1.00)]
• b) [(0.75)³(0.25)] ÷ [(0.50)²(0.75)]
• c) [(0.75)³(0.25)] ÷ [(0.50)²(0.25)]
• d) [(0.75)³(0.25)] ÷ [(0.75)²(0.25)]

Answer:  [(0.75)³(0.25)] ÷ [(0.50)²(0.75)]

Question:  The dissociation constants for acetic acid and HCN at 25°C are 1.5×10^–5 and 4.5×10^–10 respectively. The equilibrium constant for the equilibrium,would be

• a) 3.0 × 10^–5 
• b) 3.0 × 10^–4
• c) 3.0 × 10⁴
• d) 3.0 × 10⁵

Answer: 3.0 × 10⁴

Question:  The ionization constant of ammonium hydroxide is 1.77 × 10^–5 at 298 K. Hydrolysis constant of ammonium chloride is

• a) 6.50 × 10^–12
• b) 5.65 × 10^–13
• c) 5.65 × 10^–12
• d) 5.65 × 10^–10

Answer: 5.65 × 10^–10

Question:  What is the [OH^–] in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M Ba(OH)₂? 

• a) 0.40 M
• b) 0.0050 M
• c) 0.12 M
• d) 0.10 M

Answer: 0.10 M

Question:  Equal volumes of three acid solutions of pH–3, 4 and 5 are mixed in a vessel. What will be the H⁺ ion concentration in the mixture? 

• a) 1.11 × 10^–3 M 
• b) 1.11 × 10^–4 M 
• c) 3.7 × 10^–4 M
• d) 3.7 × 10^–3 M

Answer:  3.7 × 10^–4 M

Question:  The value of equilibrium constant of the reaction

is 8.0. The equilibrium constant of the reaction,

• a)

  

• b)

  

• c)

  

• d) 16

Answer:

Question:  Equal volumes of three acid solutions of pH–3, 4 and 5 are mixed in a vessel. What will be the H⁺ ion concentration in the mixture?

• a) 1.11 × 10^–3 M 
• b) 1.11 × 10^–4 M 
• c) 3.7 × 10^–4 M
• d) 3.7 × 10^–3 M

Answer: 3.7 × 10^–4 M

Question:  The values of K_P1 and K_P2

for the reactionsare in ratio of 9:1. If degree of dissociation X and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio 

• a) 1 : 1
• b) 3 : 1
• c) 1 : 9
• d) 36 : 1

Answer: 36 : 1

Question:  If the concentration of OH^– ions in the reaction 

1/4 times, then equilibrium concentration of Fe³⁺ will increase by 

• a) 4 times
• b) 8 times
• c) 16 times
• d) 64 times

Answer: 64 times

Question: Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest pH?

• a) CaCl₂
• b) SrCl₂
• c) BaCl₂ 
• d) MgCl₂

Answer: BaCl₂ 

Question:  Calculate the pOH of a solution at 25°C that contains 1×10^–10 M of hydronium ions, i.e., H₃O⁺

• a) 1.000
• b) 7.000
• c) 4.000
• d) 9.000

Answer: 4.000

Question:  A weak acid, HA has a K_a of 1.00 × 10^–5. If 0.100 mol of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to 

• a) 0.100%
• b) 99.0%
• c) 1.00%
• d) 99.9%

Answer: 1.00%

Question: Which one of the following ionic species has the greatest proton affinity to form stable compound ?

• a)

  

• b) HS^–
• c) NH₂^–
• d) F^–

Answer:   NH₂^–

Question: Which of the following pairs constitutes a buffer ?

• a) HNO₂ and NaNO₂
• b) NaOH and NaCl
• c) HNO₃ and NH₄NO₃   
• d) HCl and KCl

Answer:  HNO₂ and NaNO₂