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.
Last updated
573 questions · page 20 of 29
- A. Effective collision
- B. Useless collision
- C. Ineffective collision
- D. All of the above
Explanation: In a chemical reaction, molecules must collide with a certain amount of energy and in the correct orientation for the reaction to occur.
Correct answer: Effective collision- A. 1 s-1
- B. 0.3 s-1
- C. 0.6 s-1
- D. 0.9 s-1
Explanation: The rate of a reaction is typically expressed in terms of moles per unit volume per unit time.
Correct answer: 0.6 s-1- A. Reaction rate
- B. Reaction mechanism
- C. Factors that affect the reaction rate
- D. All of them
Explanation: Option D is the correct choice as it includes all the elements that fall under the domain of chemical kinetics.
Correct answer: All of them384. A substance that alters the rate of chemical reaction without being consumed is reaction is called:
- A. Catalyst
- B. Reactant
- C. Product
- D. Activated complex
Explanation: A catalyst is a substance that can be added to a reaction to increase the reaction rate without getting consumed in the process.
Correct answer: Catalyst- A. First order
- B. Third order
- C. Second order
- D. Zero order
Explanation: Order of reaction is determined experimentally.The radioactive disintegration of 23892U is determined to be a first order reaction.
Correct answer: First order- A. First order
- B. Third order
- C. Second order
- D. Pseudo-first order
Explanation: Option D, "Pseudo-first order," is correct for hydrolytic reactions. Hydrolytic reactions can involve multiple steps and species, making…
Correct answer: Pseudo-first order- A. 0
- B. 1
- C. 1.5
- D. 2
Explanation: The overall rate of a reaction is determined by the slowest step in the mechanism, which is often referred to as the rate-determining…
Correct answer: 2388. A first order reaction has k = 102 Sec-1, the time required to convert 20 g of it to 5 g will be:
- A. 138.6 s
- B. 238.6 s
- C. 346.5 s
- D. 693 s
Explanation: In a first-order reaction, the time required to convert a certain amount of substance can be calculated using the equation t = (1/k) ×…
Correct answer: 138.6 s- A. H
- B. E
- C. Ea
- D. Collision frequency
Explanation: Option C, "Ea" (Activation Energy), is the correct answer. A catalyst is a substance that speeds up a chemical reaction by providing an…
Correct answer: Ea- A. CH4 + Cl2
- B. CH3COOH + C2H5OH
- C. AgNO3 + NaCI
- D. C + 2H2
Explanation: Option C, "AgNO3 + NaCl," is the fastest reaction among the given options.
Correct answer: AgNO3 + NaCI- A. Lack light
- B. Lack catalyst
- C. Have high Ea
- D. Have low [R]
Explanation: The rate of a chemical reaction is directly proportional to the concentration of the reactants.
Correct answer: Have low [R]- A. Zero order
- B. 1st order
- C. 2nd order
- D. 3rd order
Explanation: Option A, "Zero order," is correct because in a zero-order reaction, the rate of the reaction is independent of the concentration of the…
Correct answer: Zero order- A. Order, k
- B. k, Rate
- C. Rate, t 1/2
- D. t 1/2
Explanation: Option C, "Rate, t1/2," is correct for a second-order reaction.In a second-order reaction, the rate of the reaction is directly…
Correct answer: Rate, t 1/2- A. First order
- B. Second order
- C. Third order
- D. Zero order
Explanation: In a second-order reaction, the rate of the reaction is directly proportional to the square of the concentration of the reactant.
Correct answer: Second order- A. First order
- B. Second order
- C. Third order
- D. Zero order
Explanation: The decomposition of N2O5 follows first-order kinetics. This means that the rate of the reaction is directly proportional to the…
Correct answer: First order396. Amount of product formed increases with time, this statement is true for reactions with kinetics:
- A. 1st order
- B. Zero order
- C. 3rd order
- D. Any order
Explanation: This option is correct because the statement "Amount of product formed increases with time" can be true for reactions of any order.
Correct answer: Any order- A. s-1
- B. mol dm-3s-1
- C. mol dm-3s1
- D. mol-2dm+6s-1
Explanation: The unit for the rate constant of a second order reaction is moldm-3s-1For a second order reaction, rate = k[A]2 moldm-3s-1=…
Correct answer: mol dm-3s-1- A. Will double the reaction
- B. Will increase the reaction
- C. Will decrease the reaction
- D. Will not alter the concentration of reactant
Explanation: Doubling the pressure in a liquid phase reaction typically does not alter the concentration of the reactant.
Correct answer: Will not alter the concentration of reactant- A. Fruitful collision
- B. Effective collision
- C. Both A and B
- D. Ineffective collision
Explanation: Option C, "Both a and b," is correct because both "Fruitful collision" and "Effective collision" refer to the type of collision that…
Correct answer: Both A and B- A. 10
- B. 100
- C. 1000
- D. Infinity
Explanation: Option D, "Infinity," is correct for a first-order reaction because any reaction never completely converts all of the reactant to product…
Correct answer: Infinity