This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Chemistry Part I > Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics – Quiz 8 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 8 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. The fraction of molecules with energy equal to or greater than activation energy is given by: A) Arrhenius equation. B) Collision theory. C) Henry's law. D) Van't Hoff equation. Show Answer Correct Answer: A) Arrhenius equation. 2. The catalyst alters the rate of a chemical reaction by, A) Providing an alternative pathway with a lower Ea. B) Providing a surface on which the molecules react. C) Increasing the frequencies of collisions between molecules. D) Changing the products formed in the direction of the reaction. Show Answer Correct Answer: A) Providing an alternative pathway with a lower Ea. 3. 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. 4. 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 is shorter at lower temperature. C) The half-life depends on the concem9of the reactant. 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. 5. 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$_{0 }$-kt. B) C-C$_{0}$ = 0. C) C/C$_{0}$ = k. D) C = C$_{0 }$-k. Show Answer Correct Answer: A) C = C$_{0 }$-kt. 6. The activated complex is also called the ..... A) Reaction mechanism. B) Reaction rate. C) Transition state. D) Reaction order. Show Answer Correct Answer: C) Transition state. 7. 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. 8. The time of half change of a first order reaction is ..... initial concentration. A) Proportional to. B) Independent of. C) Equal to. D) Inversely proportional to. Show Answer Correct Answer: B) Independent of. 9. ..... is determined experimentally A) Avagadro s law. B) Boyle s law. C) Charle s law. D) Rate law. Show Answer Correct Answer: D) Rate law. 10. What happens to the rate of a reaction if the concentration of a reactant is doubled in a second-order reaction? A) Rate quadruples. B) Rate decreases. C) Rate remains the same. D) Rate doubles. Show Answer Correct Answer: A) Rate quadruples. 11. 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. 12. How does activation energy affect the speed of a chemical reaction? A) Activation energy has no impact on the speed of a reaction. B) Activation energy is irrelevant to the speed of chemical reactions. C) Lower activation energy results in faster reactions. D) Higher activation energy leads to slower reactions. Show Answer Correct Answer: C) Lower activation energy results in faster reactions. 13. 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. 14. On increasing the temperature by 10 K, the rate of reaction becomes almost double. The most appropriate reason is A) Increase in the energy of collisions. B) Increase in the number of collisions. C) Almost double the number of molecules crossing the energy barrier. D) Decrease in activation energy. Show Answer Correct Answer: A) Increase in the energy of collisions. 15. What is the order of reaction decomposition of Ammonia on platinum surface is A) Second order reaction. B) First order reaction. C) Zero order reaction. D) Fractional order reaction. Show Answer Correct Answer: B) First order reaction. 16. The graph of ln k vs. 1/T is: A) Linear with a negative slope. B) Parabolic. C) Exponential. D) Linear with a positive slope. Show Answer Correct Answer: A) Linear with a negative slope. 17. 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) Neither exothermic nor endothermic. B) Exothermic. C) Endothermic. D) Independent of temperature. Show Answer Correct Answer: B) Exothermic. 18. In a chemistry experiment, Nora, William, and Olivia are observing a series of reactions. They are trying to determine which step is the rate determining one. What should they look for? A) The slowest reaction in the series. B) The simplest reaction in the series. C) The fastest reaction in the series. D) The main reaction involving the major reactant. Show Answer Correct Answer: A) The slowest reaction in the series. 19. In a first-order reaction, the rate of reaction is directly proportional to which of the following? A) The concentration of the reactant. B) The square of the concentration of the reactant. C) The inverse of the concentration of the reactant. D) The cube of the concentration of the reactant. Show Answer Correct Answer: A) The concentration of the reactant. 20. According to Bronsted-Bjerrum theory of effect of ionic strength on degradation rate, if the charges of the reacting species are the same, adding an electrolyte to a liquid formulation may cause stability problems. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 21. The rate of gaseous reaction remains unchanged when volume of the vessel is doubled. The order of the reaction is A) 0. B) 1. C) 2. D) 3. Show Answer Correct Answer: A) 0. 22. Which of the following statements concerning zero-order degradation is false? A) ITS CONCENTRATION REMAINS UNCHANGED WITH RESPECT TO TIME. B) Zero order reaction does not depend on concentration. C) Zero order rate constant units is mass/time. D) None of the above. Show Answer Correct Answer: A) ITS CONCENTRATION REMAINS UNCHANGED WITH RESPECT TO TIME. 23. In an experiment, the rate of reaction is measured at different temperatures. What is the most likely effect of increasing the temperature on the rate of reaction? A) The rate decreases. B) The rate increases. C) The rate remains the same. D) The rate becomes zero. Show Answer Correct Answer: B) The rate increases. 24. A reaction has the rate law:Rate = k [A][B].What is the overall order of reaction? A) 1st. B) 2nd. C) 3rd. D) 4th. Show Answer Correct Answer: B) 2nd. 25. The rate of a chemical reaction is NOT affected by which of the following: A) Temperature. B) Concentration. C) Particle size (surface area). D) All of these affect reaction rates. Show Answer Correct Answer: D) All of these affect reaction rates. 26. Radioactivity of a sample (z = 22) decreases 90% after 10 years. What will be the half-life of the sample? A) 3 years. B) 5 years. C) 2 years. D) 10 years. Show Answer Correct Answer: A) 3 years. 27. The reaction CHCl$_{3}$(g) + Cl$_{2}$(g)? CCl$_{4}$(g) + HCl(g) has the following rate law:Rate = k[CHCl$_{3}$][Cl$_{2}$]. If the concentration of CHCl$_{3}$ is increased by a factor of five while the concentration of Cl$_{2}$ is kept the same, the rate will a) Double. b) Increase by a factor of five. c) Triple. d) Decrease by a factor of one-fifth. A) C. B) B. C) D. D) A. Show Answer Correct Answer: B) B. 28. Which of the following is not a characteristic of a catalyst? A) It changes the equilibrium constant. B) It increases the rate of reaction. C) It does not affect the Gibbs energy. D) It alters the reaction path. Show Answer Correct Answer: A) It changes the equilibrium constant. 29. In a reaction, A + B $\rightarrow$ Product, rate is doubled when the concentration of B is doubled, and rate increases by a factor of 8 when the concentrations of both the reactants (Aand B) are doubled, rate law for the reaction can be written as A) Rate = k[A]$^{2}$[B]. B) Rate = k[A][B]$^{2}$. C) Rate = k[A]$^{2}$[B]$^{2}$. D) Rate = k[A] [B]. Show Answer Correct Answer: A) Rate = k[A]$^{2}$[B]. 30. Define activation energy and its importance in kinetics. A) Activation energy is the total energy released during a reaction. B) Activation energy is the minimum energy needed for a reaction to occur, and it is important in kinetics as it affects the reaction rate. C) Activation energy has no effect on the speed of a reaction. D) Activation energy is the energy required to break chemical bonds only. Show Answer Correct Answer: B) Activation energy is the minimum energy needed for a reaction to occur, and it is important in kinetics as it affects the reaction rate. 31. Reaction rate is a change in ..... per unit time. A) Volume. B) Concentration. C) State. D) Mass. Show Answer Correct Answer: B) Concentration. 32. This type of kinetics is observed when the conc. or amount of the reactant is constant, either by excess initial concentration or by rapid replenishment of the reactant. A) Pseudo zero-order. B) Pseudo first-order. C) All the above. D) None of the above. Show Answer Correct Answer: A) Pseudo zero-order. 33. The rate law for a reaction between the substances A and B is given by Rate = k [A]$^{n}$ [B]$^{m}$ .On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be A) N-m. B) 1/2$^{n+m}$. C) M+n. D) 2$^{n-m}$. Show Answer Correct Answer: D) 2$^{n-m}$. 34. What is a zero-order reaction? A) A zero-order reaction has a reaction rate that increases with reactant concentration. B) A zero-order reaction is characterized by a variable reaction rate depending on temperature. C) A zero-order reaction requires a catalyst to proceed. D) A zero-order reaction has a constant reaction rate that does not depend on the concentration of reactants. Show Answer Correct Answer: D) A zero-order reaction has a constant reaction rate that does not depend on the concentration of reactants. 35. For a zero order reaction, the half life depends on the initial concentration [C$_{o}$] of the reactant as A) [C$_{o}$]$^{1/2}$. B) [C$_{o}$]. C) [C$_{o}$]$^{-1}$. D) [C$_{o}$]$^{o}$. Show Answer Correct Answer: D) [C$_{o}$]$^{o}$. 36. The expression that correlate rate of the reaction with concentration of the reactant is called A) Rate law. B) Rate expression. C) Rate order. D) Both 1 and 2. Show Answer Correct Answer: D) Both 1 and 2. 37. The overall order of a reaction is defined as: A) The sum of the stoichiometric coefficients. B) The sum of the exponents in the rate law expression. C) The maximum number of molecules involved in any elementary step. D) None of these. Show Answer Correct Answer: B) The sum of the exponents in the rate law expression. 38. For the elementary step of a chemical reaction:A + H$_{2}$O $\rightarrow$ Brate = [A]$^{1}$What is the (i) Molecularity and (ii) Order of the reaction. A) 2, 1. B) 1, 1. C) 2, 2. D) 1, 2. Show Answer Correct Answer: A) 2, 1. 39. If 'a' is the initial concentration of the reactant, the half life period of the n$^{th}$ order reaction is proportional to A) A$^{1-n}$. B) A$^{n+1}$. C) A$^{n}$. D) A$^{n-1}$. Show Answer Correct Answer: A) A$^{1-n}$. 40. What is the rate equation of following chemical reaction?2NaOH + H$_{2}$SO$_{4}$ $\rightarrow$ Na$_{2}$SO$_{4}$ + 2H$_{2}$O A) Rate = k.[NaOH]$^{2}$.[H$_{2}$SO$_{4}$]. B) Rate = k.[NaOH].[H$_{2}$SO$_{4}$]. C) Rate = k.[NaOH]$^{2}$.[H$_{2}$SO$_{4}$]$^{2}$. D) Rate = k.[NaOH]$^{2}$. Show Answer Correct Answer: A) Rate = k.[NaOH]$^{2}$.[H$_{2}$SO$_{4}$]. 41. What is the relationship between rate of reaction and temperature? A) Directly proportional. B) No relationship. C) Inversely proportional. D) Jointly proportional. Show Answer Correct Answer: A) Directly proportional. 42. Increasing the temperature in a reaction lowers the activation energy. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 43. The rate law expresses the reactant of the reaction A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 44. Which one of the following is a first order, overall reaction A) K$_{1}$= 1.000 M s$^{-1}$. B) K$_{1}$= 10.7 s$^{-1}$. C) K$_{1}$= 5403.2 M$^{1/2}$ s$^{1/2}$. D) K$_{1}$= 1.23 x 10$^{-6}$ M$^{-1}$ s$^{-1}$. Show Answer Correct Answer: B) K$_{1}$= 10.7 s$^{-1}$. 45. Which one of the following is NOT a characteristic of a zero-order drug decomposition reaction? A) The rate of reaction is constant. B) The units of the rate constant (k) are time-1. C) The half-life of the drug decomposition is directly proportional to the initial concentration of API. D) The rate of reaction is independent of the concentration of any of the reactants. Show Answer Correct Answer: B) The units of the rate constant (k) are time-1. 46. What will happen if no salt bridge were used in an electrochemical cell ( like Zn-Cu) A) The circuit will run and current will flow. B) The circuit will run but current stops. C) The circuit will stop working hence current also inform. D) Alllu lay lo Welomce moviee. Show Answer Correct Answer: C) The circuit will stop working hence current also inform. 47. Which will not generally increase the rate of a chemical reaction? A) Increasing the size of solid reactant particles. B) Increasing the surface area of solid reactant particles. C) Decreasing the activation energy. D) Increasing the concentration of the reactant particles. Show Answer Correct Answer: A) Increasing the size of solid reactant particles. 48. A ..... may increase or decrease the rate of the reaction A) Reactant. B) Product. C) Catalyst. D) Both 1 and 2. Show Answer Correct Answer: C) Catalyst. 49. Which statement is false about molecularity of a reaction? A) Molecularity of a reaction can have integral values only. B) Molecularity of a reaction can be zero. C) In complex reaction, molecularity is equal to the number of molecules present in the rate law equation. D) Molecularity is a theoretical concept. Show Answer Correct Answer: B) Molecularity of a reaction can be zero. 50. In a reversible reaction reaction, the rate of degradation is expressed as A) -dB/dt=Kr[A] + kf[B]. B) -dB/dt=Kf[B]-kr[A]. C) DB/dt=Kf[A]-kr[B]. D) -dB/dt=Kf[A]-kr[B]. Show Answer Correct Answer: D) -dB/dt=Kf[A]-kr[B]. 51. More collisions correspond to a: A) Faster reaction rate. B) Slower reaction rate. C) Constant reaction rate. D) None of the above. Show Answer Correct Answer: A) Faster reaction rate. 52. What is chemical kinetic? A) Study of the chemical rate and reaction mechanism. B) Study of the reaction between reaction rate and concentration of the reactant. C) Study of the reaction rate and surface area of the reactants. D) None of the above. Show Answer Correct Answer: A) Study of the chemical rate and reaction mechanism. 53. What is the difference between average rate and instantaneous rate? A) Instantaneous rate is an average over time. B) Average rate is always higher than instantaneous rate. C) Average rate is over an interval; instantaneous rate is at a specific moment. D) Average rate is calculated at a single point in time. Show Answer Correct Answer: C) Average rate is over an interval; instantaneous rate is at a specific moment. 54. For the reaction A giving B, the rate of a reaction becomes sixty four times when concentration of A is increased four times. what is the order of the reaction? A) 3. B) 4. C) 2. D) 1. Show Answer Correct Answer: A) 3. 55. What is required for a chemical reaction to occur? A) Standard temperature and pressure. B) A catalyst added to the reaction system. C) Effective collisions between reactant particles. D) An equal number of moles of reactants and products. Show Answer Correct Answer: C) Effective collisions between reactant particles. 56. For a zero order reaction, the half life depends on the initial concentration [C$_{o}$] of the reactant as3A $\rightarrow$ B+ CIt would be a zero order reaction when: A) The reaction rate is proportional to the square of concentration of A. B) The reaction rate remains the same at any concentration of A. C) The reaction rate remains unchanged at any concentration of B and C. D) The reaction rate doubles if concentration of B is increased to double. Show Answer Correct Answer: B) The reaction rate remains the same at any concentration of A. 57. In the elementary reaction 2A + B $\rightarrow$ A2B, if the concentration of A is doubled and that of B is halved, then the rate of the reaction will A) Increase 2 times. B) Decrease 2 times. C) Remain the same. D) Increase 4 times. Show Answer Correct Answer: D) Increase 4 times. 58. $\ln\left[A\right]=-kt+\ln\left[A\right]o$ A) 3rd order reaction. B) 1st order reaction. C) 2nd order reaction. D) 0 order reaction. Show Answer Correct Answer: B) 1st order reaction. 59. It is defined as the degree of coldness or hotness of an object A) Enthalpy. B) Internal energy. C) Temperature. D) Heat. Show Answer Correct Answer: C) Temperature. 60. To measure rate of reaction, we can monitor change in which of the following? A) Reactants only. B) Products only. C) Reactants or products. D) None of the above. Show Answer Correct Answer: C) Reactants or products. ← PreviousNext →Related QuizzesScience QuizzesClass 12 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 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books