This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics – Quiz 4 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 4 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What will be the fraction of molecules having energy equal to or greater than activation energy, Ea? A) K. B) A. C) Ae-Ea/Rt. D) E-Ea/Rt. Show Answer Correct Answer: D) E-Ea/Rt. 2. What is the condition for a reaction to be feasible according to thermodynamics? A) DG is constant. B) DG < 0. C) DG > 0. D) DG = 0. Show Answer Correct Answer: B) DG < 0. 3. In any first order reaction, as the reaction proceeds at constant temperature, which describes the corresponding effects on k (the rate constant) and rate? A) K remains the same; rate decreases. B) K and rate both remain the same. C) K remains the same; rate increases. D) K decreases; rate remains the same. Show Answer Correct Answer: A) K remains the same; rate decreases. 4. Reaction rates can change with A) Temperature. B) The addition of catalyst. C) Reactant concentration. D) All of these above. Show Answer Correct Answer: D) All of these above. 5. Rate of the reaction is usually doubled or tripled as the temperature is A) Increased. B) Decreased. C) Both. D) None. Show Answer Correct Answer: A) Increased. 6. The rate of a reaction is doubled when the concentration of reactant A is doubled. What is the order of the reaction with respect to A? A) Zero order. B) First order. C) Second order. D) Third order. Show Answer Correct Answer: B) First order. 7. In terms of collision theory, a reaction occurs when the molecules collide with sufficient energy to break the bonds already in place. What is this energy called? A) Activation energy. B) Reaction mechanism. C) Activity series. D) Concentration gradient. Show Answer Correct Answer: A) Activation energy. 8. In general, an increase in temperature of 10$^\circ$C will have what effect on reaction rate:A. Double the rate B. Half the rate C. Triple the rate D. Increase the rate but not by a specific amount A) A. B) B. C) C. D) D. Show Answer Correct Answer: A) A. 9. For an elementary reaction 2A + B $\rightarrow$C + D, the molecularity is A) Zero. B) One. C) Two. D) Three. Show Answer Correct Answer: D) Three. 10. In powdered state rate of the reaction is maximum is due to A) Increase in surface area. B) Decrease in surface area. C) Increase in density. D) Decrease in density. Show Answer Correct Answer: A) Increase in surface area. 11. Which of the following are true of reaction rates?I. The overall rate law is determined by the fastest step of a reactionII. The presence of a catalyst will increase the number of molecules entering the transition stateIII. An increase in temperature will increase the rate of a reactionIV. Decreasing the concentration of reactants will increase the rate at which products yield A) II+III+IV. B) I+IV. C) II + III. D) I+II+III. Show Answer Correct Answer: C) II + III. 12. Which of the following could be used to follow the rate of a reaction?I. Change in temperature as the reaction proceedsII. Change in colour as the reaction proceedsIII. Change in electrical conductivity as the reaction proceeds A) I and II only. B) I and IIl only. C) Il and IIl only. D) I, ll and IIl only. Show Answer Correct Answer: D) I, ll and IIl only. 13. How does the orientation of molecules affect collisions? A) Molecular orientation influences the effectiveness of collisions and the likelihood of reactions. B) Molecular orientation has no impact on reaction rates. C) Collisions are only affected by temperature, not orientation. D) Molecules collide randomly regardless of their orientation. Show Answer Correct Answer: A) Molecular orientation influences the effectiveness of collisions and the likelihood of reactions. 14. What is the relationship between rate of reaction and concentration of reactants? A) No relationship. B) Directly proportional. C) Inversely proportional. D) Jointly proportional. Show Answer Correct Answer: B) Directly proportional. 15. Which among the following is a false statement? A) Rate of zero order reaction is independent of initial concentration of reactant. B) Half life of a third order reaction is inversely proportional to square of initial concentration of the reactant. C) Molecularity of a reaction may be zero or fraction. D) For a first order reaction, t1/2 = 0.693/K. Show Answer Correct Answer: C) Molecularity of a reaction may be zero or fraction. 16. Units of second order rate constant = ..... A) Mol L$^{-1}$ time$^{-1}$. B) L mol$^{-1}$ time$^{-1}$. C) L$^{2}$ mol$^{-2}$ time$^{-1}$. D) Time$^{-1}$. Show Answer Correct Answer: B) L mol$^{-1}$ time$^{-1}$. 17. A thermodynamically favorable reaction proceeds spontaneously. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 18. How does temperature influence the activation energy of a reaction? A) Temperature increases the rate of reaction by providing more molecules with energy to overcome the activation energy barrier. B) Higher temperatures increase the activation energy required for a reaction. C) Temperature decreases the rate of reaction by lowering the energy of molecules. D) Temperature has no effect on the activation energy of a reaction. Show Answer Correct Answer: A) Temperature increases the rate of reaction by providing more molecules with energy to overcome the activation energy barrier. 19. Catalysts permit reactions to happen with a ..... activiation energy. A) Lower. B) Higher. C) All the above. D) None of the above. Show Answer Correct Answer: A) Lower. 20. What is explaining behaviors of a system at equilibrium? A) Avagadro's Law. B) Boyles Law. C) Le Chatelier Principle. D) Collusion Theory. Show Answer Correct Answer: C) Le Chatelier Principle. 21. Units of rate is ..... A) M/s. B) Mol/s. C) M.s. D) S/M. Show Answer Correct Answer: A) M/s. 22. Determine order of reaction for the reactant A and B based on this rate law:Rate = K [A]$^{2}$[B]$^{1}$ A) First order and [B] first order. B) First order and [B] second order. C) Second order and [B] first order. D) Second order and [B] second order. Show Answer Correct Answer: C) Second order and [B] first order. 23. How does a catalyst influence the rate of a reaction? A) A catalyst increases the rate of a reaction by lowering the activation energy. B) A catalyst changes the products of the reaction. C) A catalyst has no effect on the rate of a reaction. D) A catalyst decreases the rate of a reaction by increasing the activation energy. Show Answer Correct Answer: A) A catalyst increases the rate of a reaction by lowering the activation energy. 24. Half life period for a zero order reaction is directly proportional to the initial concentration of the reactant. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 25. If we dissolve less solute than the amount needed to form a saturated solution, the solution is unsaturated. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. ← PreviousNext →Related QuizzesClass 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 1Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 2Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 3Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 5Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 6Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 7Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 8Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 9Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 10Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books