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 5 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 5 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. The strengths of intermolecular forces in different substances vary over a wide range but are generally much weaker than intramolecular forces-ionic, metallic or covalent bonds. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 2. The half-life of a reaction is the time in which ..... A) The concentration of a product is reduced to one half of its initial concentration. B) The concentration of a reactant is reduced to one half of its initial concentration. C) All the above. D) None of the above. Show Answer Correct Answer: B) The concentration of a reactant is reduced to one half of its initial concentration. 3. Which of the following expression is the accurate depiction of the rate of degradation of triazolam? Triazolam ..... Kf ..... hydrolysis product Kr A) -d[Triazolam]/dt = Kr[Triazolam]-Kf[Hydrolysis Product]. B) -d[Triazolam]/dt = Kf[Triazolam]-Kr[Hydrolysis Product]. C) D[Triazolam]/dt = Kr[Triazolam]-Kf[Hydrolysis Product]. D) -d[Triazolam]/dt = Kf[Triazolam] + Kr[Hydrolysis Product]. Show Answer Correct Answer: B) -d[Triazolam]/dt = Kf[Triazolam]-Kr[Hydrolysis Product]. 4. For two particles to react when they collide what must be true according to collision theory? A) They must both have the same kinetic energy. B) All their chemical bonds must be broken. C) They must collide with the correct geometry or orientation. D) They must be in the gaseous or liquid state. Show Answer Correct Answer: C) They must collide with the correct geometry or orientation. 5. What is the significance of the collision theory in kinetics? A) Collision theory states that all collisions result in reactions. B) Collision theory is significant in kinetics as it provides a framework for understanding how and why reactions occur, influencing reaction rates. C) Collision theory only applies to gas reactions. D) Collision theory is unrelated to reaction rates. Show Answer Correct Answer: B) Collision theory is significant in kinetics as it provides a framework for understanding how and why reactions occur, influencing reaction rates. 6. When the concentration of reactant molecules is increased, the rate of reaction increases. The best explanation is:As the reactant concentration increases, (a) the average kinetic energy of molecules increases.(b) the frequency of molecular collisions increases.(c) the rate constant increases.(d) the activation energy increases. A) B. B) D. C) A. D) C. Show Answer Correct Answer: A) B. 7. Explain the role of surface area in reaction rates. A) Surface area has no effect on reaction rates whatsoever. B) Increasing surface area slows down the reaction by creating barriers. C) A larger surface area increases reaction rates by allowing more collisions between reactant particles. D) A larger surface area decreases reaction rates by reducing collisions. Show Answer Correct Answer: C) A larger surface area increases reaction rates by allowing more collisions between reactant particles. 8. Catalyst act by ..... A) No effect. B) Increasing activation energy. C) Providing alternate pathway. D) Changing reactant. Show Answer Correct Answer: C) Providing alternate pathway. 9. A drug is given intravenously and the blood concentration measured at 1 and 4 hours are 26 and 18 mcg/ml. What is the half life using first order kinetics? A) 5.7 days. B) 8 days. C) 5.7 hours. D) 7.5 hours. Show Answer Correct Answer: C) 5.7 hours. 10. In the reaction 2A $\rightarrow$ B + C, if the rate of disappearance of A is 0.60 M/s, what is the rate of appearance of B? A) 1.20 M/s. B) 0.60 M/s. C) 0.30 M/s. D) 0.15 M/s. Show Answer Correct Answer: C) 0.30 M/s. 11. The first order rate constant for the decomposition of 0.5 M compound A at 100$^{o}$C is 0.03 min$^{-1}$. Calculate the half-life of A. A) 1.5 min. B) 66.7 min. C) 8.3 min. D) 23.1 min. Show Answer Correct Answer: D) 23.1 min. 12. What is the energy needed for reactant particles to change into products? A) Conversion. B) Kinetic. C) Potential. D) Activation. Show Answer Correct Answer: D) Activation. 13. The value of rate constant of a pseudo first order reaction ..... A) Depends on the concentration of reactants present in small amount. B) Depends on the concentration of reactants present in excess. C) Is independent of the concentration of reactants. D) Depends only on temperature. Show Answer Correct Answer: A) Depends on the concentration of reactants present in small amount. 14. In the presence of a catalyst, the heat evolved or absorbed during the reaction A) Increases. B) Decreases. C) Unchanged. D) None of the above. Show Answer Correct Answer: C) Unchanged. 15. Which statement is not correct regarding the function of a catalyst? A) It lowers the energy of the product, causing the reaction to be more exothermic. B) It changes the mechanism of a reaction. C) It affects the rate of a chemical reaction. D) It lowers the activation energy. Show Answer Correct Answer: A) It lowers the energy of the product, causing the reaction to be more exothermic. 16. A pseudo zero-order reaction is one in which:THE RATE DEPENDS ON THE CONCENTRATION OF ONE OF THE REACTANTS, WHICH IS EITHER VERY LARGE OR IS A CONSTANT A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 17. Given the reaction inside a container of CO$_{2}$(g) + H$_{2}$O(g) $\rightarrow$ A) The rate increases. B) The rate decreases. C) It has no effect. D) The rate will remain the same. Show Answer Correct Answer: A) The rate increases. 18. Among the solids, the rate increases with ..... in particle size A) Increase. B) Decrease. C) Remains same. D) None. Show Answer Correct Answer: B) Decrease. 19. For 2A + B $\rightarrow$ 2C, the rate of production of C has been found to be 12 M/s. During that reaction, the rate of reaction was? A) 12 M/s. B) 6 M/s. C) 24 M/s. D) Cannot tell without more data. Show Answer Correct Answer: B) 6 M/s. 20. A compound has a half-life of 14 min. How much time will it take a 12 mol sample to decay to 1.5 mol? A) 28 min. B) 56 min. C) 42 min. D) 14 min. Show Answer Correct Answer: C) 42 min. 21. What is meant by the order of a reaction? A) The order of a reaction is determined by the temperature of the reaction. B) The order of a reaction is the sum of the powers of the concentration terms in the rate law. C) The order of a reaction is the concentration of the reactants at equilibrium. D) The order of a reaction refers to the time it takes for the reaction to complete. Show Answer Correct Answer: B) The order of a reaction is the sum of the powers of the concentration terms in the rate law. 22. The following are the kinds of intermolecular interactions are involved in solution formation EXCEPT: A) Solvent-solvent. B) Solvent-solute. C) Solute-solute. D) Solution-solvent. Show Answer Correct Answer: D) Solution-solvent. 23. A possible rate law for a third overall order of a reaction is ..... A) Rate = k [A]$^{3}$ [B]. B) Rate = k [A][B]$^{3}$. C) Rate = k [A]$^{2}$[B]$^{2}$. D) Rate = k [A]$^{2}$[B]. Show Answer Correct Answer: D) Rate = k [A]$^{2}$[B]. 24. The half-life of a substance in a certain enzyme catalysed reaction is 138 s. The time required for the concentration of the substance to fall from 1.28 mg L$^{-1}$ to 0.04 mg L$^{-1}$, is A) 414 s. B) 690 s. C) 552 s. D) 276 s. Show Answer Correct Answer: B) 690 s. 25. A reaction follows the rate law Rate = k[A][B]. What happens to the rate when [A] is doubled and [B] is tripled? A) Increases 6 times. B) Increases 2 times. C) Increases 3 times. D) Unchanged. Show Answer Correct Answer: A) Increases 6 times. 26. Catalyst catalyses the ..... A) Spontaneous reactions. B) Nonspontaneous reactions. C) Both. D) None. Show Answer Correct Answer: A) Spontaneous reactions. 27. The unit of rate constant for the second order reaction will be ..... A) Mol$^{0.5}$ L$^{-0.5}$ s$^{-1}$. B) Mol L$^{-1}$ s$^{-1}$. C) L mol$^{-1}$ s$^{-1}$. D) S$^{-1}$. Show Answer Correct Answer: C) L mol$^{-1}$ s$^{-1}$. 28. Which of the following statements about catalysts is true:a. catalysts do not appear in the balanced equation b. catalysts reduce the activation energy for a reaction c. biological catalysts are called enzymes d. catalysts do not alter the mechanism of the reaction and never appear in the rate law A) A, B. B) A, B, C. C) B, C, D. D) A, B, D. Show Answer Correct Answer: B) A, B, C. 29. A+B $\rightarrow$C+D $\Delta$H =-202kj/molHow can above reaction be classified in terms of energy exchange during chemical change? A) Endothermic reaction. B) Exothermic reaction. C) Transthermal reaction. D) Combination reaction. Show Answer Correct Answer: B) Exothermic reaction. 30. Which type of catalyst is used in the Haber process for ammonia synthesis? A) Cu. B) Ni. C) Fe. D) Pt. Show Answer Correct Answer: C) Fe. 31. A type of system which do not allow exchange of energy and matter with its surroundings A) Isolated. B) Universal. C) Closed. D) Open. Show Answer Correct Answer: A) Isolated. 32. What is meant by a reaction being first order with respect to a reactant? A) The rate of the reaction is directly proportional to the concentration of that reactant. B) The rate of the reaction is inversely proportional to the concentration of that reactant. C) The rate of the reaction decreases as the concentration of that reactant increases. D) The rate of the reaction is independent of the concentration of that reactant. Show Answer Correct Answer: A) The rate of the reaction is directly proportional to the concentration of that reactant. 33. Will the rate constant of a reaction depends upon T if the activation energy of the reaction is zero? A) Rate constant become zero. B) Rate constant become dependent upon the temperature if Ea is zero. C) Can't say. D) Rate constant become independent upon the temperature if Ea is zero. Show Answer Correct Answer: D) Rate constant become independent upon the temperature if Ea is zero. 34. In a reaction mechanism, if the first step is slow and the second step is fast, what can be inferred about the overall rate law? A) It depends on both steps. B) It depends only on the fast step. C) It depends only on the slow step. D) It cannot be determined. Show Answer Correct Answer: B) It depends only on the fast step. 35. Given 3A + B $\rightarrow$ 2CWhich statement is TRUE A) Concentration A will be increase and concentration B will be decrease after reaction. B) Concentration A will be increase and concentration C will be decrease after reaction. C) Concentration B will be decrease and concentration C will be increase after reaction. D) Concentration B will be decrease and concentration A will be increase after reaction. Show Answer Correct Answer: C) Concentration B will be decrease and concentration C will be increase after reaction. 36. What is the term for the speed of a reaction? A) Reaction rate. B) Reaction order. C) Reaction mechanism. D) Reaction constant. Show Answer Correct Answer: A) Reaction rate. 37. Usually lowering the temperature will slow down a reaction. A) False. B) True. C) All the above. D) None of the above. Show Answer Correct Answer: B) True. 38. The rate law of the reaction 2N$_{2}$O$_{5}$ $\rightarrow$ 2NO$_{2}$ + O$_{2}$ is A) R = k[NO$_{2}$]$^{4 }$[O$_{2}$]. B) R = k[N$_{2}$O$_{5}$ ]0. C) R = k[N$_{2}$O$_{5}$ ]. D) R = k[N$_{2}$O$_{5}$ ]$^{2}$. Show Answer Correct Answer: D) R = k[N$_{2}$O$_{5}$ ]$^{2}$. 39. What is the point group of water A) C3V. B) C5V. C) C2v. D) C4V. Show Answer Correct Answer: C) C2v. 40. Unit for rate constant is one of the striking differences between a zero and first order process? A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 41. The time taken for 10% completion of a first order reaction is 20 mins .Then for 19% completion, the reaction will take A) 50 mins. B) 40 mins. C) 60 mins. D) 30 mins. Show Answer Correct Answer: B) 40 mins. 42. For which reactions the rate and rate constant are identical? A) Zero order reaction. B) First order reaction. C) Third order reaction. D) Pseudo first order reaction. Show Answer Correct Answer: A) Zero order reaction. 43. For the reaction mechanism:Step 1:A+B$\rightarrow$C (slow)Step 2:C$\rightarrow$D (fast)The rate law is: A) Rate =k[C]. B) Rate =k[A][B]. C) Rate =k[A]$^{2}$[B]. D) Rate =k[D]. Show Answer Correct Answer: B) Rate =k[A][B]. 44. Which of the following is the example of pseudo first order reactions? A) Decomposition of ammonium nitrite. B) Conversion of N-chloroacetanilide into p-chloroacetanilide. C) Decomposition of hydrogen peroxide. D) Hydrolysis of ethylacetate. Show Answer Correct Answer: D) Hydrolysis of ethylacetate. 45. What is the difference between zero-order and first-order reactions? A) Zero-order reactions have a rate that increases with time; first-order reactions have a constant rate. B) Zero-order reactions are faster than first-order reactions at all concentrations. C) Zero-order reactions have a constant rate; first-order reactions have a rate proportional to reactant concentration. D) Zero-order reactions depend on temperature; first-order reactions do not. Show Answer Correct Answer: C) Zero-order reactions have a constant rate; first-order reactions have a rate proportional to reactant concentration. 46. What is the effect of concentration on the rate of a reaction? A) Increasing concentration has no effect on the rate of a reaction. B) Decreasing concentration typically increases the rate of a reaction. C) Concentration only affects the temperature of the reaction. D) Increasing concentration typically increases the rate of a reaction. Show Answer Correct Answer: D) Increasing concentration typically increases the rate of a reaction. 47. A chemical reaction that requires energy is a A) Exothermic reaction. B) Endothermic reaction. C) Over reaction. D) None of the above. Show Answer Correct Answer: B) Endothermic reaction. 48. A first order reaction takes 40 min for 30% decomposition. t$_{1/2}$ will be A) 52.5 min. B) 46.2 min. C) 77.7 min. D) 22.7 min. Show Answer Correct Answer: C) 77.7 min. 49. During a chemistry experiment, Scarlett, Charlotte, and Aiden are trying to understand the rate law expression. They are discussing the quantity of K in the expression. What is the correct statement about K? A) It is independent of the concentration of the reactants. B) It is called the Arrhenius constant. C) It is dimensionless. D) It is independent of temperature. Show Answer Correct Answer: A) It is independent of the concentration of the reactants. 50. Acids yield hydrogen ions while bases yield hydroxyl ions. The aforementioned statement agrees with; A) Arrhenius theory. B) Bronsted-Lowry theory. C) Lewis theory. D) None of the choices. Show Answer Correct Answer: A) Arrhenius theory. 51. A reaction is found to be second order with respect to carbon monoxide. If the concentration of carbon monoxide is doubled, the rate of reaction ..... A) Increases by a factor of 4. B) Remains unchanged. C) Is reduced by a factor of 2. D) Doubles. Show Answer Correct Answer: A) Increases by a factor of 4. 52. What factors can influence the rate of a chemical reaction? A) Color, volume, time, light, humidity. B) Temperature, concentration, surface area, catalyst, pressure. C) All the above. D) None of the above. Show Answer Correct Answer: B) Temperature, concentration, surface area, catalyst, pressure. 53. Olivia wants to keep her leftovers fresh for a longer time. Which of the following actions involves controlling the rate of a chemical reaction? A) Using sunscreen. B) Refrigerating food. C) Wearing safety goggles. D) Washing hands. Show Answer Correct Answer: B) Refrigerating food. 54. The sum of the exponents to which the molar concentration in the rate law equation are raised is called A) Order of reaction. B) Molecularity of reaction. C) Speed of the reaction. D) None of the above. Show Answer Correct Answer: A) Order of reaction. 55. Which of the following is an appropriate dimension for the zero order rate? A) Hour-1. B) Mg/hour. C) Mole. D) Gram. Show Answer Correct Answer: B) Mg/hour. 56. 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, t$_{1/2}$=0.693K A) C. B) D. C) A. D) B. Show Answer Correct Answer: A) C. 57. What two factors govern whether a collision between reacting particles will be effective? A) Orientation and potential energy. B) Kinetic energy and temperature. C) Kinetic energy and orientation. D) Potential energy and kinetic energy. Show Answer Correct Answer: C) Kinetic energy and orientation. 58. Half-life of a zero order reaction depends on both the initial concentration or amount of the substance and the rate of reaction A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 59. How does the rate of a forward reaction compare to the rate of a reverse reaction at equilibrium? A) The reverse reaction is always faster than the forward reaction. B) The forward reaction is always faster than the reverse reaction. C) The rates of the forward and reverse reactions are unequal at equilibrium. D) The rates of the forward and reverse reactions are equal at equilibrium. Show Answer Correct Answer: D) The rates of the forward and reverse reactions are equal at equilibrium. 60. Which of these does not influence the rate of reaction? A) Temperature of the reaction. B) Molecularity of the reaction. C) Concentration of the reactants. D) Nature of the reactants. Show Answer Correct Answer: B) Molecularity of the reaction. ← 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 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 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books