This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics – Quiz 23 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part I) Chapter 4 Chemical Kinetics Quiz 23 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Limestone chunks are reaction with hydrochloric acid solution at constant temperature with average speed. If we crash the chunks of limestone into powder how would speed of reaction change? A) Reaction speeds up. B) Reaction does not change. C) Reaction slows down. D) Reaction stops. Show Answer Correct Answer: A) Reaction speeds up. 2. Which of the following is a special and distinct class of catalysts comprised of naturally occurring biological substances? A) Homogeneous catalyst. B) Heterogeneous catalyst. C) Enzyme. D) Inhibitor. Show Answer Correct Answer: C) Enzyme. 3. What is the half-life of a first-order reaction dependent on? A) Initial concentration. B) Rate constant. C) Pressure only. D) Temperature only. Show Answer Correct Answer: B) Rate constant. 4. For the reaction A + 2 B$\rightarrow$C, the reaction rate is doubled if the concentration of A is doubled. The rate is increased by four times when concentrations of both A and B are increased by four times. The order of reaction is A) 3. B) 0. C) 1. D) 2. Show Answer Correct Answer: C) 1. 5. For the reaction 4D + E $\rightarrow$ 3F, how does the rate of disappearance of D compare to the rate of production of F? A) The rate of disappearance of D is the same as the rate of appearance of F. B) The rate of disappearance of D is 3/4 the rate of appearance of F. C) The rate of disappearance of D is twice the rate of appearance of F. D) The rate of disappearance of D is 4/3 the rate of appearance of F. Show Answer Correct Answer: D) The rate of disappearance of D is 4/3 the rate of appearance of F. 6. Collision theory is satisfactory for: A) First order reactions. B) Zero order reactions. C) Bimolecular elementary reaction. D) Any order reactions. Show Answer Correct Answer: C) Bimolecular elementary reaction. 7. What is the relationship between temperature and reaction rate? A) Temperature has no effect. B) Higher temperature increases rate. C) Higher temperature decreases rate. D) Temperature only affects solids. Show Answer Correct Answer: B) Higher temperature increases rate. 8. Explain the concept of half-life in chemical kinetics. A) Half-life is the time taken for a reactant to double its concentration. B) Half-life refers to the total time a reaction takes to complete. C) Half-life is the time required for a product to form in a reaction. D) Half-life is the time taken for the concentration of a reactant to reduce to half its initial value. Show Answer Correct Answer: D) Half-life is the time taken for the concentration of a reactant to reduce to half its initial value. 9. The rate constant is doubles on the increasing temperature from 310K to 350K. What is the activation energy (in kJ mol-1) for this reaction? A) 12.3. B) 15.6. C) 25.8. D) 29.2. Show Answer Correct Answer: B) 15.6. 10. If the half-life of a first-order reaction is 20 min, the time required for 87.5% decomposition is: A) 20 min. B) 40 min. C) 60 min. D) 80 min. Show Answer Correct Answer: C) 60 min. 11. Samuel is observing how quickly a tablet dissolves in water. What aspect of the reaction is Samuel studying? A) Whether a reaction will occur. B) The energy released by a reaction. C) The rate at which a reaction occurs. D) The balance of chemical equations. Show Answer Correct Answer: C) The rate at which a reaction occurs. 12. Which of the following expression is the accurate depiction of the rate of degradation of hydrocortisone alcohol, P1? hydrocortisone hemisuccinate D $\rightarrow$ hydrocortisone alcohol P1 $\rightarrow$ 17-dihydroxyacetone products P2 A) -d[P1]/dt = K2[P2]-K1[P1]. B) D[P1]/dt = K2[P1] + K1[D]. C) -d[P1]/dt = K2[P1]-K1[D]. D) -d[P1]/dt = K1[D]-K2[P1]. Show Answer Correct Answer: C) -d[P1]/dt = K2[P1]-K1[D]. 13. What is the relationship between reaction rate and the order of a reaction? A) Reaction rate is not affected by the order of a reaction. B) Reaction rate is directly proportional to the order of a reaction. C) Reaction rate is inversely proportional to the order of a reaction. D) Reaction rate is proportional to the square of the order of a reaction. Show Answer Correct Answer: B) Reaction rate is directly proportional to the order of a reaction. 14. Activation energy of a chemical reaction can be determined by ..... A) Determining the rate constant at standard temperature. B) Determining the rate constants at two temperatures. C) Determining probability of collision. D) Using catalyst. Show Answer Correct Answer: B) Determining the rate constants at two temperatures. 15. Which is equal to the slope of a line drawn tangentto the concentration vs time curve at that time A) Average rate. B) Instantaneous rate. C) Slow rate. D) Fast rate. Show Answer Correct Answer: B) Instantaneous rate. 16. Write the rate law and order for the following reaction:AB$_{2}$ + C$_{2}$ $\rightarrow$ AB$_{2}$C + C (slow)AB$_{2}$ + C $\rightarrow$ AB$_{2}$C (Fast) A) R= K [AB$_{2}$] [C$_{2}$]order = 2. B) R= K [AB$_{2}$] [C$_{2}$]order = 3. C) R= K [AB$_{2}$]order = 2. D) R= K [AB$_{2}$]$^{2 }$[C$_{2}$]order = 2. Show Answer Correct Answer: A) R= K [AB$_{2}$] [C$_{2}$]order = 2. 17. A first order reaction has a half-life length of 10 minutes. In 100 minutes, what proportion of the response will be completed? A) 25%. B) 50%. C) 99.9%. D) 75%. Show Answer Correct Answer: C) 99.9%. 18. Which of the following factors affect the rate of a reaction according to collision theory?I. The frequency of the collisions between reactant particles.II. The orientation of the particles when they collide.III. The number of reactant particles with E greater than or equal to Ea. A) I and II only. B) I and III only. C) II and III only. D) L, II and III only. Show Answer Correct Answer: D) L, II and III only. 19. The activation energy for the forward reaction is Ea, and the enthalpy change ($\Delta$H) is-40 kJ/mol. What is the activation energy for the backward reaction? A) Ea + 40 kJ/mol. B) Ea-40 kJ/mol. C) 40 kJ/mol. D) Ea. Show Answer Correct Answer: A) Ea + 40 kJ/mol. 20. Which statement will be increase the rate of reaction A) Temperature must be lowered. B) Dilute concentration. C) Lower pressure. D) Smaller size particles. Show Answer Correct Answer: D) Smaller size particles. 21. What is the slope of the graph of concentration vs. Time for 0 order reaction A) -k. B) K. C) 1/k. D) K/2.023. Show Answer Correct Answer: A) -k. 22. Consider the following rate law:Rate = k[A]$^{n}$[B]$^{m}$How are the exponents n and m determined? A) By using balanced chemical equation. B) By using the subscripts for the formulas. C) By educated guess. D) By experiment. Show Answer Correct Answer: D) By experiment. 23. The number of molecules of the reactants taking part in a single step of the reaction is indicative of A) Order of a reaction. B) Molecularity of a reaction. C) Fast step of the mechanism of a reaction. D) Half-life of the reaction. Show Answer Correct Answer: B) Molecularity of a reaction. 24. What is the unit for rate constant, K if rate law:Rate = k [A] A) S$^{-1}$. B) M s$^{-1}$. C) M$^{-1 }$s$^{-1}$. D) M$^{-2 }$s$^{-1}$. Show Answer Correct Answer: A) S$^{-1}$. 25. The slope of a ln k vs. 1/T plot is: A) + Ea/R. B) -Ea/R. C) Ln A. D) Ln Ea. Show Answer Correct Answer: B) -Ea/R. ← 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