R4RIN – MCQs, Mock Tests | CBES Board Class 10 Chemistry CHEMICAL EQUILIBRIUM MCQS

In equilibrium constant expression, the concentration of products is taken in/on the

1. right side
2. left side
3. numerator
4. denominator

✅ Correct Answer: 3

Unit of equilibrium constant for H2 + I2 2HI is

1. no units
2. mol dm-3
3. dm3mol-1
4. none of above

✅ Correct Answer: 1

What is the representation of a reversible reaction?

1. single arrow
2. double arrows
3. bar
4. none of above

✅ Correct Answer: 2

The rate at which the reaction proceeds is directly proportional to the product of the active masses of

1. products
2. reactants
3. catalysts
4. none of above

✅ Correct Answer: 2

Which of the following is the correct representation for active mass?

1. ( )
2. { }
3. [ ]
4. none of above

✅ Correct Answer: 3

Unit of the equilibrium constant for H2 + CO2 H2O + CO is

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 1

What percentage of ammonia is given after cooling the equilibrium mixture by the Haber process?

1. 20 percent
2. 33 percent
3. 100 percent
4. 98 percent

✅ Correct Answer: 4

Due to the high concentration of reactants, the rate of the forward reaction is

1. lowest
2. moderate
3. highest
4. minimal

✅ Correct Answer: 3

In the reverse reaction SO3 decomposes in to

1. S and O
2. S and O2
3. S2 and O
4. SO2 and O2

✅ Correct Answer: 4

Unit of the equilibrium constant for N2 + O2 2NO is

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 1

The relationship by which the values that relate amounts of products to reactants at equilibrium can be determined is called

1. law of conservation of mass
2. law of chemical reactions
3. law of mass action
4. active mass

✅ Correct Answer: 3

The term active mass shows the concentration of reactants and products in

1. mol.dm-3 for a dilute solution
2. mol.cm-3 for a dilute solution
3. mol.dm-3 for a concentrated solution
4. mol.cm-3 for a concentrated solution

✅ Correct Answer: 1

The equilibrium constant can be used to determine the equilibrium concentration of equilibrium mixture knowing the

1. final concentration of products
2. final concentration of reactants
3. initial concentration of reactants
4. initial concentration of products

✅ Correct Answer: 3

When diluting acid always add

1. water to acid
2. acid to water
3. acid to oxygen
4. hydrogen to acid

✅ Correct Answer: 2

The state at which forward and reverse reactions occur at the same rate is

1. equilibrium
2. unstable equilibrium
3. not in equilibrium
4. neutral equilibrium

✅ Correct Answer: 1

Which of the following is used as a catalyst in the contact process?

1. Zeolite
2. Ag
3. Pd
4. Pt

✅ Correct Answer: 4

Which process is used for the large scale production of sulphuric acid?

1. contact process
2. Haber process
3. sulphuric acid process
4. none of above

✅ Correct Answer: 1

The rate at which the reaction proceeds is directly related to

1. active masses of reactants
2. sum of active masses of reactants
3. product of active masses of reactants
4. ratio of active masses of reactants

✅ Correct Answer: 3

Unit of the equilibrium constant for 2NO + O2 2NO2 is

1. no units
2. mol dm-3
3. dm3mol-1
4. dm3mol-2

✅ Correct Answer: 3

Unit of equilibrium constant for PCl5 PCl3 + Cl2

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 2

What is denoted by the subscript c in Kc?

1. chemical equilibrium
2. chemical reaction
3. molar concentration at equilibrium
4. rate of chemical reaction

✅ Correct Answer: 3

What percentage of ammonia is produced at equilibrium by the Haber process?

1. 20 percent
2. 33 percent
3. 100 percent
4. 99 percent

✅ Correct Answer: 2

In Habers process, the amount of ammonia yields is

1. 0.4
2. 0.9
3. 0.33
4. 0.22

✅ Correct Answer: 3

What is established when the rate of evaporation equals the rate of condensation?

1. equality
2. equilibrium
3. reversible reaction
4. irreversible reaction

✅ Correct Answer: 2

The rate at which a substance reacts is directly proportional to its

1. product
2. active mass
3. reactant
4. catalysts

✅ Correct Answer: 2

The reactions in which reactants react to form products and simultaneously products reverse back into reactants are called

1. reversible reactions
2. irreversible reaction
3. spontaneous reactions
4. non spontaneous reactions

✅ Correct Answer: 1

The equilibrium constant can be used to

1. predict direction of chemical reaction
2. predict extent of chemical reaction
3. determine the equilibrium concentration of mixture
4. all of above

✅ Correct Answer: 4

The process by which ammonia is produced by the reaction of nitrogen with hydrogen at 200 atm pressure and in the presence of a catalyst is called

1. contact process
2. recovery of ammonia
3. calcination
4. Haber process

✅ Correct Answer: 4

If a change is imposed in concentration, temperature or pressure on a chemical system at equilibrium, the system responds in a way that the change is

1. not opposed
2. opposed
3. rapidly increased
4. slowly increased

✅ Correct Answer: 2

Which of the following statements about catalysts is not true?

1. they speed up a chemical reaction
2. they reduce the time taken to reach equilibrium
3. they have effect on the position of equilibrium once it is reached
4. they have no effect on the position of equilibrium one it is reached

✅ Correct Answer: 3

A substance which increases the rate of reaction is called

1. catalyst
2. reactant
3. product
4. coordinator

✅ Correct Answer: 1

If the concentration, temperature, and pressure is changed, the system responds in a way that

1. follows the change
2. opposes the change
3. does not change at all
4. encourages the change

✅ Correct Answer: 2

The conditions for equilibrium of concentration of reactant and products will be the same if

1. temperature is constant
2. pressure or volume is constant
3. concentration of products and reactants are same
4. all of above

✅ Correct Answer: 4

A reversible reaction

1. always completes
2. never goes to completion
3. spontaneous reactions
4. non spontaneous reactions

✅ Correct Answer: 2

What is the term used for a state of a chemical reaction in which forward and reverse reactions take place at the same rate?

1. chemical equilibrium
2. stable reaction
3. reversible reaction
4. forward reaction

✅ Correct Answer: 1

Which of the following has made it possible to get the maximum amount of products?

1. Le Chatelliers principle
2. Charles law
3. Boyles law
4. Snells law

✅ Correct Answer: 1

Unit of the equilibrium constant for N2O4 2NO2 is

1. mol dm-4
2. mol dm-3
3. dm3mol-1
4. mol dm-3

✅ Correct Answer: 2

Which of the following statements about the equilibrium constant is not true?

1. it is very useful
2. it is independent of the initial concentration of reactants
3. it does not depend upon temperature
4. it depends upon temperature

✅ Correct Answer: 3

The law of mass action was proposed by

1. Newton
2. Le Chatellier
3. C.M Guldberg and P.Waage
4. Lewis

✅ Correct Answer: 3

Which of the following reactions causes acid droplets to spew in all directions?

1. acid base reaction
2. combustion
3. vigorous reaction
4. decomposition

✅ Correct Answer: 3

Kf and Kr are

1. equilibrium constants
2. reaction constants
3. chemical constants
4. rate constants

✅ Correct Answer: 4

Substances which increase the rate of a chemical reaction are called

1. proteins
2. single cell protein
3. enzymes
4. catalysts

✅ Correct Answer: 4

The ratio of the product of the concentration of products to the product of the concentration of reactants is called

1. equilibrium constant
2. equilibrium ratio
3. reverse reaction
4. forward reaction

✅ Correct Answer: 1

In equilibrium constant expression, the concentration of reactants is taken in/on the

1. right side
2. left side
3. numerator
4. denominator

✅ Correct Answer: 4

Unit of the equilibrium constant for CO + 2H2 CH3OH is

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 4

What is represented by each figure within a square bracket in the equilibrium expression?

1. concentration in mol.dm-3
2. volume of products
3. mass of products
4. mass of reactants

✅ Correct Answer: 1

In equilibrium constant expression, the concentration of products is taken in/on the

1. right side
2. left side
3. numerator
4. denominator

✅ Correct Answer: 3

Unit of equilibrium constant for H2 + I2 2HI is

1. no units
2. mol dm-3
3. dm3mol-1
4. none of above

✅ Correct Answer: 1

What is the representation of a reversible reaction?

1. single arrow
2. double arrows
3. bar
4. none of above

✅ Correct Answer: 2

The rate at which the reaction proceeds is directly proportional to the product of the active masses of

1. products
2. reactants
3. catalysts
4. none of above

✅ Correct Answer: 2

Which of the following is the correct representation for active mass?

1. ( )
2. { }
3. [ ]
4. none of above

✅ Correct Answer: 3

Unit of the equilibrium constant for H2 + CO2 H2O + CO is

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 1

What percentage of ammonia is given after cooling the equilibrium mixture by the Haber process?

1. 20 percent
2. 33 percent
3. 100 percent
4. 98 percent

✅ Correct Answer: 4

Due to the high concentration of reactants, the rate of the forward reaction is

1. lowest
2. moderate
3. highest
4. minimal

✅ Correct Answer: 3

In the reverse reaction SO3 decomposes in to

1. S and O
2. S and O2
3. S2 and O
4. SO2 and O2

✅ Correct Answer: 4

Unit of the equilibrium constant for N2 + O2 2NO is

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 1

The relationship by which the values that relate amounts of products to reactants at equilibrium can be determined is called

1. law of conservation of mass
2. law of chemical reactions
3. law of mass action
4. active mass

✅ Correct Answer: 3

The term active mass shows the concentration of reactants and products in

1. mol.dm-3 for a dilute solution
2. mol.cm-3 for a dilute solution
3. mol.dm-3 for a concentrated solution
4. mol.cm-3 for a concentrated solution

✅ Correct Answer: 1

The equilibrium constant can be used to determine the equilibrium concentration of equilibrium mixture knowing the

1. final concentration of products
2. final concentration of reactants
3. initial concentration of reactants
4. initial concentration of products

✅ Correct Answer: 3

When diluting acid always add

1. water to acid
2. acid to water
3. acid to oxygen
4. hydrogen to acid

✅ Correct Answer: 2

The state at which forward and reverse reactions occur at the same rate is

1. equilibrium
2. unstable equilibrium
3. not in equilibrium
4. neutral equilibrium

✅ Correct Answer: 1

Which of the following is used as a catalyst in the contact process?

1. Zeolite
2. Ag
3. Pd
4. Pt

✅ Correct Answer: 4

Which process is used for the large scale production of sulphuric acid?

1. contact process
2. Haber process
3. sulphuric acid process
4. none of above

✅ Correct Answer: 1

The rate at which the reaction proceeds is directly related to

1. active masses of reactants
2. sum of active masses of reactants
3. product of active masses of reactants
4. ratio of active masses of reactants

✅ Correct Answer: 3

Unit of the equilibrium constant for 2NO + O2 2NO2 is

1. no units
2. mol dm-3
3. dm3mol-1
4. dm3mol-2

✅ Correct Answer: 3

Unit of equilibrium constant for PCl5 PCl3 + Cl2

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 2

What is denoted by the subscript c in Kc?

1. chemical equilibrium
2. chemical reaction
3. molar concentration at equilibrium
4. rate of chemical reaction

✅ Correct Answer: 3

What percentage of ammonia is produced at equilibrium by the Haber process?

1. 20 percent
2. 33 percent
3. 100 percent
4. 99 percent

✅ Correct Answer: 2

In Habers process, the amount of ammonia yields is

1. 0.4
2. 0.9
3. 0.33
4. 0.22

✅ Correct Answer: 3

What is established when the rate of evaporation equals the rate of condensation?

1. equality
2. equilibrium
3. reversible reaction
4. irreversible reaction

✅ Correct Answer: 2

The rate at which a substance reacts is directly proportional to its

1. product
2. active mass
3. reactant
4. catalysts

✅ Correct Answer: 2

The reactions in which reactants react to form products and simultaneously products reverse back into reactants are called

1. reversible reactions
2. irreversible reaction
3. spontaneous reactions
4. non spontaneous reactions

✅ Correct Answer: 1

The equilibrium constant can be used to

1. predict direction of chemical reaction
2. predict extent of chemical reaction
3. determine the equilibrium concentration of mixture
4. all of above

✅ Correct Answer: 4

The process by which ammonia is produced by the reaction of nitrogen with hydrogen at 200 atm pressure and in the presence of a catalyst is called

1. contact process
2. recovery of ammonia
3. calcination
4. Haber process

✅ Correct Answer: 4

If a change is imposed in concentration, temperature or pressure on a chemical system at equilibrium, the system responds in a way that the change is

1. not opposed
2. opposed
3. rapidly increased
4. slowly increased

✅ Correct Answer: 2

Which of the following statements about catalysts is not true?

1. they speed up a chemical reaction
2. they reduce the time taken to reach equilibrium
3. they have effect on the position of equilibrium once it is reached
4. they have no effect on the position of equilibrium one it is reached

✅ Correct Answer: 3

A substance which increases the rate of reaction is called

1. catalyst
2. reactant
3. product
4. coordinator

✅ Correct Answer: 1

If the concentration, temperature, and pressure is changed, the system responds in a way that

1. follows the change
2. opposes the change
3. does not change at all
4. encourages the change

✅ Correct Answer: 2

The conditions for equilibrium of concentration of reactant and products will be the same if

1. temperature is constant
2. pressure or volume is constant
3. concentration of products and reactants are same
4. all of above

✅ Correct Answer: 4

A reversible reaction

1. always completes
2. never goes to completion
3. spontaneous reactions
4. non spontaneous reactions

✅ Correct Answer: 2

What is the term used for a state of a chemical reaction in which forward and reverse reactions take place at the same rate?

1. chemical equilibrium
2. stable reaction
3. reversible reaction
4. forward reaction

✅ Correct Answer: 1

Which of the following has made it possible to get the maximum amount of products?

1. Le Chatelliers principle
2. Charles law
3. Boyles law
4. Snells law

✅ Correct Answer: 1

Unit of the equilibrium constant for N2O4 2NO2 is

1. mol dm-4
2. mol dm-3
3. dm3mol-1
4. mol dm-3

✅ Correct Answer: 2

Which of the following statements about the equilibrium constant is not true?

1. it is very useful
2. it is independent of the initial concentration of reactants
3. it does not depend upon temperature
4. it depends upon temperature

✅ Correct Answer: 3

The law of mass action was proposed by

1. Newton
2. Le Chatellier
3. C.M Guldberg and P.Waage
4. Lewis

✅ Correct Answer: 3

Which of the following reactions causes acid droplets to spew in all directions?

1. acid base reaction
2. combustion
3. vigorous reaction
4. decomposition

✅ Correct Answer: 3

Kf and Kr are

1. equilibrium constants
2. reaction constants
3. chemical constants
4. rate constants

✅ Correct Answer: 4

Substances which increase the rate of a chemical reaction are called

1. proteins
2. single cell protein
3. enzymes
4. catalysts

✅ Correct Answer: 4

The ratio of the product of the concentration of products to the product of the concentration of reactants is called

1. equilibrium constant
2. equilibrium ratio
3. reverse reaction
4. forward reaction

✅ Correct Answer: 1

In equilibrium constant expression, the concentration of reactants is taken in/on the

1. right side
2. left side
3. numerator
4. denominator

✅ Correct Answer: 4

Unit of the equilibrium constant for CO + 2H2 CH3OH is

1. no units
2. mol dm-3
3. dm3mol-1
4. [mol dm-3]-2

✅ Correct Answer: 4

What is represented by each figure within a square bracket in the equilibrium expression?

1. concentration in mol.dm-3
2. volume of products
3. mass of products
4. mass of reactants

✅ Correct Answer: 1