This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics – Quiz 18 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 18 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. A catalyst is added to a reaction mixture. Which of the following is a likely outcome? A) The activation energy of the reaction increases. B) The reaction rate decreases. C) The catalyst is consumed in the reaction. D) The reaction reaches equilibrium faster. Show Answer Correct Answer: D) The reaction reaches equilibrium faster. 2. Which is a true statement about two Maxwell-Boltzman energy distribution curvesdrawn for a fixed amount of gas at two different temperatures, T K and (T+10) K? A) Both curves will peak at the same height. B) The area under both curves will be the same. C) Both curves will have the same number of particles with higher energy. D) He average energy for both curves will be the same. Show Answer Correct Answer: B) The area under both curves will be the same. 3. Under the same reaction conditions, initial concentration of 1.386 mol L$^{-1}$ of a substance becomes half in 40 seconds and 20 seconds through first order and zero order kinetics respectively. Ratio of the rate constants k$_{1}$/k$_{0}$ for first order (k$_{1}$) and zero order (k$_{0}$) of the reaction is A) 0.5 mol$^{-1}$ L. B) 1 mol$^{-1}$ L. C) 1.5 mol$^{-1}$ L. D) 2 mol$^{-1}$ L. Show Answer Correct Answer: A) 0.5 mol$^{-1}$ L. 4. As the concentration of reacting particles increases, the rate of reaction generally A) Decreases. B) Increases. C) Remains the same. D) None of the above. Show Answer Correct Answer: B) Increases. 5. An endothermic reaction absorbs heat, and an exothermic reaction releases heat. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 6. A chemical reaction that produces energy is a /an A) Endothermic reaction. B) Exothermic reaction. C) Energy. D) Chemical reaction. Show Answer Correct Answer: B) Exothermic reaction. 7. Zero-order reaction DOES NOT CHANGE WITH CONCENTRATION. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 8. The fraction of molecules with energy equal to or greater than activation energy is given by: A) Arrhenius equation. B) Collision theory. C) Van't Hoff equation. D) Henry's law. Show Answer Correct Answer: A) Arrhenius equation. 9. The catalyst alters the rate of a chemical reaction by, A) Providing an alternative pathway with a lower Ea. B) Changing the products formed in the direction of the reaction. C) Providing a surface on which the molecules react. D) Increasing the frequencies of collisions between molecules. Show Answer Correct Answer: A) Providing an alternative pathway with a lower Ea. 10. Which of the following plots will show a linear relationship for a first order reaction? A) [A] vs time. B) $^{1}$/$_{[A]}$ vs time. C) Ln[A] vs time. D) [A]$^{2}$ vs time. Show Answer Correct Answer: C) Ln[A] vs time. 11. Which of the following statements regarding the half-life of first order reaction is true? A) The half-life is affected by pressure. B) The half-life depends on the concem9of the reactant. C) The half-life is shorter at lower temperature. D) At the end of fourth half-life, the percentage of element left is 6.25% of the original quantity. Show Answer Correct Answer: D) At the end of fourth half-life, the percentage of element left is 6.25% of the original quantity. 12. If C is the concentration of A at any time and C$_{0}$ is its concentration at time t = 0 then, for zero order reaction, rate equation can be written as: A) C-C$_{0}$ = 0. B) C = C$_{0 }$-k. C) C/C$_{0}$ = k. D) C = C$_{0 }$-kt. Show Answer Correct Answer: D) C = C$_{0 }$-kt. 13. The activated complex is also called the ..... A) Reaction rate. B) Reaction mechanism. C) Transition state. D) Reaction order. Show Answer Correct Answer: C) Transition state. 14. The rate law of any chemical reaction A) Must be determined experimentally. B) Can be deduced based on the stoichiometry of the reaction. C) Changes based on the condition of the experiment. D) I don't know. Show Answer Correct Answer: A) Must be determined experimentally. 15. The time of half change of a first order reaction is ..... initial concentration. A) Proportional to. B) Inversely proportional to. C) Independent of. D) Equal to. Show Answer Correct Answer: C) Independent of. 16. ..... is determined experimentally A) Rate law. B) Boyle s law. C) Charle s law. D) Avagadro s law. Show Answer Correct Answer: A) Rate law. 17. What happens to the rate of a reaction if the concentration of a reactant is doubled in a second-order reaction? A) Rate remains the same. B) Rate doubles. C) Rate quadruples. D) Rate decreases. Show Answer Correct Answer: C) Rate quadruples. 18. A first order of reaction is a reaction whose rate depends on the reactant concentration raised to 2nd power A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 19. How does activation energy affect the speed of a chemical reaction? A) Activation energy has no impact on the speed of a reaction. B) Higher activation energy leads to slower reactions. C) Lower activation energy results in faster reactions. D) Activation energy is irrelevant to the speed of chemical reactions. Show Answer Correct Answer: C) Lower activation energy results in faster reactions. 20. What factors affect the rate of a chemical reaction? A) Temperature, concentration, surface area, catalysts, and nature of reactants. B) Pressure of the environment. C) Color of reactants. D) Humidity levels. Show Answer Correct Answer: A) Temperature, concentration, surface area, catalysts, and nature of reactants. 21. How does temperature influence reaction rates? A) Temperature has no effect on reaction rates. B) Higher temperatures slow down reaction rates. C) Lower temperatures decrease reaction rates. D) Higher temperatures generally increase reaction rates. Show Answer Correct Answer: D) Higher temperatures generally increase reaction rates. 22. On increasing the temperature by 10 K, the rate of reaction becomes almost double. The most appropriate reason is A) Increase in the number of collisions. B) Decrease in activation energy. C) Increase in the energy of collisions. D) Almost double the number of molecules crossing the energy barrier. Show Answer Correct Answer: C) Increase in the energy of collisions. 23. What is the order of reaction decomposition of Ammonia on platinum surface is A) Zero order reaction. B) First order reaction. C) Second order reaction. D) Fractional order reaction. Show Answer Correct Answer: B) First order reaction. 24. The graph of ln k vs. 1/T is: A) Linear with a negative slope. B) Linear with a positive slope. C) Parabolic. D) Exponential. Show Answer Correct Answer: A) Linear with a negative slope. 25. The activation energies of the forward and backward reactions in the case of chemical reaction are 30.5KJ/mol and 45.4KJ/mol respectively:The reaction is: A) Exothermic. B) Endothermic. C) Neither exothermic nor endothermic. D) Independent of temperature. Show Answer Correct Answer: A) Exothermic. ← 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 4Class 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 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books