Free Reaction Kinetics MCQs with Answers
573 Reaction Kinetics MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
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573 questions · page 24 of 29
- A. Only Conclusion I is followed
- B. Only Conclusion II is followed
- C. Neither Conclusion I nor Conclusion II is followed
- D. Both Conclusion I and II are followed
- E. Either Conclusion I or Conclusion II is followed
Explanation: Both conclusions are not logically supported by the given statements. The statement that Pakistan is a multilingual country does not imply…
Correct answer: Neither Conclusion I nor Conclusion II is followed- A. 147
- B. 162
- C. 183
- D. 192
Explanation: The pattern of the series is 3 × n², where n is the term number. The terms are 3×1², 3×2², 3×3², and so on.
Correct answer: 147- A. True
- B. False
- C. Uncertain
- D. None of these
Explanation: If Cliff is older than Tanya, and Tanya is older than Eric, then the age order is Cliff > Tanya > Eric.
Correct answer: False- A. Statement I is the cause and statement II is its effect
- B. Statement II is the cause and statement I is its effect
- C. Both the statements I and II are independent causes
- D. Both the statements I and II are effects of independent causes
Explanation: The financial instability and inability to compete (Statement II) is a serious problem that logically cause the central banking authority…
Correct answer: Statement II is the cause and statement I is its effect- A. Only I follows
- B. Only II follows
- C. Either I or II follows
- D. Both I and II follow
Explanation: In a severe drought, the immediate priorities are life sustaining supplies like food and water (Action II).
Correct answer: Both I and II follow466. The rate of reaction
- A. (a) Increases as the reaction proceeds.
- B. (b) Decreases as the reaction proceeds.
- C. (c) Remains the same as the reaction proceeds.
- D. (d) May decrease or increase as the reaction proceeds.
Explanation: The rate of a reaction typically decreases as the reaction proceeds. At the beginning of a reaction, there are more reactants available…
Correct answer: (b) Decreases as the reaction proceeds.- A. (a) Increases the rate of forward reaction only.
- B. (b) Increases the rate of reverse reaction.
- C. (c) Increases the rate of forward but decreases the rate of backward reaction.
- D. (d) Increases the rate of forward as well as backward reaction equally.
Explanation: The correct answer for the effect of a catalyst on a reaction's rate is:(c) Increases the rate of forward but decreases the rate of…
Correct answer: (c) Increases the rate of forward but decreases the rate of backward reaction.- A. Time
- B. (b) Concentration of the reactant
- C. Temperature
- D. (d) Concentration of the product.
Explanation: Types of rates of reaction)The correct answer for the factor influencing the specific rate constant of a first-order reaction is:(c)…
Correct answer: Temperature- A. (a) The activation energy of the reaction increases
- B. (b) Concentration of the reacting molecules increases
- C. (c) Collision frequency increases
- D. (d) None of these
Explanation: The correct answer is:(c) Collision frequency increasesHere's why the other options are incorrect:(a) The activation energy of the…
Correct answer: (c) Collision frequency increases- A. Molecularity
- B. (a) Order of reaction
- C. (d) Average of reaction
- D. (c) Rate of reaction
Explanation: The correct answer is:(b) Order of reactionHere's the breakdown of why the other options are incorrect:(a) Molecularity: While the term…
Correct answer: (a) Order of reaction- A. Only products
- B. Composition of reacting substances and products
- C. Only reacting substances
- D. None of above
Explanation: The law of mass action is a fundamental principle in chemistry that relates the rate of a chemical reaction to the concentrations of the…
Correct answer: Composition of reacting substances and products- A. Its temperature is more than critical temperature
- B. Its pressure is more than critical pressure
- C. Its pressure is more than critical pressure but temperature is less than criticaltemperature
- D. It cannot be liquefied at any value of P and T.
Explanation: An ideal gas is a theoretical concept that obeys the ideal gas law (PV = nRT) perfectly.
Correct answer: Its pressure is more than critical pressure but temperature is less than criticaltemperature- A. Mg + 2HCI→ MgCI + H2
- B. MgO + 2HCI→ MgCI2+ H2O
- C. Cu +4HNO3→ Cu(NO3)2+2H2O+2NO3
- D. 2Mg + O2→2MgO
Explanation: Both Mg and O already have fixed oxidation states (0) and combine to form MgO without any change in oxidation states.Not a redox reaction.
Correct answer: 2Mg + O2→2MgO- A. Free energy change
- B. Van Der Waals equation
- C. Arrhenius equation
- D. Kinetic equation
Explanation: The effect of temperature on reaction rate is described by the Arrhenius equation.It shows that increasing temperature increases the rate…
Correct answer: Arrhenius equation- A. Increases as the reaction proceeds
- B. Decreases as the reaction proceeds
- C. Remains the same as the reaction proceeds
- D. May decrease or increase as the reaction proceeds
Explanation: The rate of reaction is dependent on the concentration of reactants. The rate of a reaction decreases as time progresses.
Correct answer: Decreases as the reaction proceeds- A. Pressure
- B. Temperature
- C. Effective collision
- D. Ineffective collision
Explanation: Activated complexes are formed as a result of effective collisions, and the term is used to refer to the state of the molecule when the…
Correct answer: Effective collision- A. Ultraviolet radiations
- B. Visible radiations
- C. Infrared radiations
- D. All of these
Explanation: This method is applicable if a reactant or a product absorbs ultraviolet, visible or infrared radiations.
Correct answer: All of these- A. Average K. E of the molecules
- B. Potential energy of the molecules
- C. Free energy of the molecules
- D. Activation energy of the molecules
Explanation: Activation energy is the minimum energy that the reactants must have to be converted into products.
Correct answer: Activation energy of the molecules- A. by increasing temperature
- B. using a suitable catalyst
- C. by an increase in activation energy
- D. by increasing concentration of reactants
Explanation: Activation energy is inversely proportional to the rate of the reaction.
Correct answer: by an increase in activation energy480. A catalyst:
- A. Increases the rate of the forward reaction only
- B. Increases the rate of both forward and reverse reactions
- C. Changes the equilibrium position
- D. Increases the rate of the reverse reaction only
Explanation: A catalyst increases the rate of both forward and reverse reaction, making the system reach equilibrium faster.
Correct answer: Increases the rate of both forward and reverse reactions