Q44.For the reaction, 2A + B → products, when the concentration of A and B both were doubled, the rate of the reaction increased from 0.3 mol L−1s−1 to 2.4 mol L−1s−1. When the concentration of A alone is doubled, the rate increased from 0.3 mol L−1s−1 to 0.6 mol L−1s−1. Which one of the following statements is correct? (1) Order of the reaction with respect to B is 2 (2) Total order of the reaction is 4 (3) Order of the reaction with respect to A is 2 (4) Order of the reaction with respect to B is 1
What This Question Tests
This question requires analyzing experimental rate data to determine the order of the reaction with respect to each reactant and the overall order of the reaction.
Concepts Tested
Formulas Used
Rate = k[A]ˣ[B]ʸ
📚 NCERT Sections This Tests
3.10 — In A Reaction Between A And B, The Initial Rate Of Reaction (R0) Was Measured
Chemistry Class 11 · Chapter 3
3.10 In a reaction between A and B, the initial rate of reaction (r0) was measured for different initial concentrations of A and B as given below: A/ mol L–1 0.20 0.20 0.40 B/ mol L–1 0.30 0.10 0.05 r0/mol L–1s–1 5.07 × 10–5 5.07 × 10–5 1.43 × 10–4 What is the order of the reaction with respect to A and B? 3.11 The following results have been obtained during the kinetic studies of the reaction: 2A + B ® C + D Experiment [A]/mol L–1 [B]/mol L–1 Initial rate of formation of D/mol L–1 min–1 I 0.1 0.1 6.0 × 10–3 II 0.3 0.2 7.2 × 10–2 III 0.3 0.4 2.88 × 10–1 IV 0.4 0.1 2.40 × 10–2 Determine the rate law and the rate constant for the reaction. 3.12 The reaction between A and B is first order with respect to A and zero order with respect to B. Fill in the blanks in the following table: Experiment [A]/ mol L–1 [B]/ mol L–1 Initial rate/ mol L–1 min–1 I 0.1 0.1 2.0 × 10–2 II – 0.2 4.0 × 10–2 III 0.4 0.4 – IV – 0.2 2.0 × 10–2 3.13 Calculate the half-life of a first order reaction from their rate constants given below: (i) 200 s–1 (ii) 2 min–1 (iii) 4 years–1 3.14 The half-life for radioactive decay of 14C is 5730 years. An archaeological artifact containing wood had only 80% of the 14C found in a living tree. Estimate the age of the sample. 3.15 The experimental data for decomposition of N2O5 [2N2O5 ® 4NO2 + O2] in gas phase at 318K are given below: t/s 0 400 800 1200 1600 2000 2400 2800 3200 102 × [N2O5]/ 1.63 1.36 1.14 0.93 0.78 0.64 0.53 0.43 0.35 mol L–1 (i) Plot [N2O5] against t. (ii) Find the half-life period for the reaction. (iii) Draw a graph between log[N2O5] and t. (iv) What is the rate law ? Chemistry 86 Reprint 2025-26 (v) Calculate the rate constant. (vi) Calculate the half-life period from k and compare it with (ii).
3.9 — A Reaction Is First Order In A And Second Order In B.
Chemistry Class 11 · Chapter 3
3.9 A reaction is first order in A and second order in B. (i) Write the differential rate equation. (ii) How is the rate affected on increasing the concentration of B three times? (iii) How is the rate affected when the concentrations of both A and B are doubled? 85 Chemical Kinetics Reprint 2025-26
3.24 — Consider A Certain Reaction A ® Products With K = 2.0 × 10 –2S–1. Calculate
Chemistry Class 11 · Chapter 3
3.24 Consider a certain reaction A ® Products with k = 2.0 × 10 –2s–1. Calculate the concentration of A remaining after 100 s if the initial concentration of A is 1.0 mol L–1.
📋 Question Details
- Chapter
- Chemical Kinetics
- Topic
- Rate law and Order of reaction
- Year
- 2019
- Shift
- 09 Jan Shift 2
- Q Number
- Q44
- Type
- MCQ
- NCERT Ref
- Class 12 Chemistry Ch 4: Chemical Kinetics
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