This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics – Quiz 9 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 9 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Abigail, Ethan, and Jackson are working on a chemistry project about the decomposition of N$_{2}$O. They found that the half-life of the reaction is 0.204 seconds. Can you help them figure out the rate constant for this first-order decomposition?Hint. t$_{1/2}$ = $\frac{0.693}{k}$ A) 5.40 s$^{-1}$. B) 0.204 s$^{-1}$. C) 3.40 s$^{-1}$. D) 2.04 s$^{-1}$. Show Answer Correct Answer: C) 3.40 s$^{-1}$. 2. Chief Minister, Government of Maharashtra A) Devendra Fadnavis. B) Shri Uddhav Thackeray. C) Narendra Modi. D) Shree Yogi ji. Show Answer Correct Answer: B) Shri Uddhav Thackeray. 3. A reaction's rate: A) Starts faster then slows down. B) Stays constant. C) Starts slower then speeds up. D) None of the above. Show Answer Correct Answer: A) Starts faster then slows down. 4. Describe the role of catalysts in chemical reactions. A) Catalysts only work in specific temperature ranges and have no effect on reaction rates. B) Catalysts are consumed in the reaction and do not affect the overall energy change. C) Catalysts decrease the rate of chemical reactions by increasing activation energy. D) Catalysts increase the rate of chemical reactions by lowering activation energy. Show Answer Correct Answer: D) Catalysts increase the rate of chemical reactions by lowering activation energy. 5. Which of the following is (are) altered when a liquid at its boiling point is converted to a gas at the same temperature?I. The size of the moleculesII. The distance between moleculesIII. The average kinetic energy of the molecules A) I only. B) II only. C) III only. D) I and II. Show Answer Correct Answer: B) II only. 6. Explain the concept of activation energy in chemical reactions. A) Activation energy is the energy released during a reaction. B) Activation energy is the minimum energy required to initiate a chemical reaction. C) Activation energy is the total energy of the reactants. D) Activation energy is the energy required to break chemical bonds. Show Answer Correct Answer: B) Activation energy is the minimum energy required to initiate a chemical reaction. 7. If the intial concentration half life of the reaction is doubled then, the order of reaction is A) 0. B) 1. C) 2. D) 3. Show Answer Correct Answer: A) 0. 8. Which one of the following is a zero order, overall reaction A) K$_{1}$= 1.000 M s$^{-1}$. B) K$_{1}$= 5403.2 M$^{1/2}$ s$^{1/2}$. C) K$_{1}$= 1.23 x 10$^{-6}$ M$^{-1}$ s$^{-1}$. D) K$_{1}$= 10.7 s$^{-1}$. Show Answer Correct Answer: A) K$_{1}$= 1.000 M s$^{-1}$. 9. Rate law for chemical reactions are determined A) By experiment. B) By examining the coefficient in balanced chemical equation. C) From equilibrium constant. D) From the rates of forward and reverse reactions of the system in equilibrium. Show Answer Correct Answer: A) By experiment. 10. Which of the following is true regarding the addition of a catalyst to a reaction? A) Rate of reverse reaction decreased. B) Energy of activated complex will decrease. C) The $\Delta$G of a reaction is decreased. D) The equilibrium favors the products upon catalyst addition. Show Answer Correct Answer: B) Energy of activated complex will decrease. 11. Which of the following is a characteristic of a zero-order reaction? A) Rate depends on concentration. B) Rate is constant. C) Rate increases with temperature. D) Rate decreases with time. Show Answer Correct Answer: B) Rate is constant. 12. A chemical reaction between iron atoms and oxygen molecules can only occur if A) The particles are heated. B) The atmospheric pressure decreases. C) There is a catalyst present. D) There are effective collisions between the particles. Show Answer Correct Answer: D) There are effective collisions between the particles. 13. The role of a catalyst is to change ..... A) Gibbs energy of reaction. B) Enthalpy of reaction. C) Activation energy of reaction. D) Equilibrium constant. Show Answer Correct Answer: C) Activation energy of reaction. 14. A substance 'A' decomposes by a first-order reaction starting initially with [A] = 2.00M and after 200min, [A] becomes 0.15M. For this reaction t1/2 is A) 53.72 min. B) 50.49 min. C) 48.45 min. D) 46.45 min. Show Answer Correct Answer: A) 53.72 min. 15. A student wished to follow the rate of the reaction between calcium carbonate and hydrochloric acid. Which of the following methods would not work? A) Measuring the volume of carbon dioxide gas evolved over time. B) Measuring the change in mass of the contents of the flask over time. C) Measuring the change in colour of the contents of the flask over time. D) Measuring the change in pH of the contents of the flask over time. Show Answer Correct Answer: C) Measuring the change in colour of the contents of the flask over time. 16. Spontaneous reactions always occur rapidly. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 17. The number of molecules of the reactants involved in a single stage of the reaction indicates A) The order of the reaction. B) The molecularity of the reaction. C) The rapid step of the reaction mechanism, and. D) The reaction half-life. Show Answer Correct Answer: B) The molecularity of the reaction. 18. What does the Arrhenius equation describe? A) The relationship between temperature and pressure. B) The relationship between concentration and reaction rate. C) The relationship between temperature and reaction rate. D) The relationship between volume and pressure. Show Answer Correct Answer: C) The relationship between temperature and reaction rate. 19. The rate of chemical reation double for every 10 degree rise of temperature. If temperature is increased by 50 degree, the rate of reaction will increase by A) 10 times. B) 32 times. C) 24 times. D) 64 times. Show Answer Correct Answer: B) 32 times. 20. The ..... states that atoms, ions, or molecules must collide in order to react. A) Transition state. B) Activation energy. C) Rate law. D) Collision theory. Show Answer Correct Answer: D) Collision theory. 21. An effective collision between reactant particles requires the particles to have the proper A) Charge and mass. B) Charge and orientation. C) Energy and mass. D) Energy and orientation. Show Answer Correct Answer: D) Energy and orientation. 22. Half life for zero order reaction depends upon A) Initial concentration of reactant. B) Initial concentration of product. C) Both 1, 2. D) None of the above. Show Answer Correct Answer: A) Initial concentration of reactant. 23. For a given rate, the unit of rate and the rate constant are the same. A) Zero order reaction. B) First order reaction. C) Second order reaction. D) Third order reaction. Show Answer Correct Answer: A) Zero order reaction. 24. Which of the following is NOT a factor affecting reaction rate? A) Temperature. B) Catalysts. C) Particle size. D) Polarity. Show Answer Correct Answer: D) Polarity. 25. For the elementary reaction M $\rightarrow$ N, the rate of disappearance of M increases by a factor of 8 upon doubling the concentration of M. The order of reaction with respect to M is A) 4. B) 3. C) 2. D) 1. Show Answer Correct Answer: B) 3. ← 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 10Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books