NTA Abhyas JEE Main2020ChemistryChemical KineticsPractice
A and B react as per the reaction A g + 2 B g → C g From the data given below identify the rate law. S .No . A M B M Rate of reaction M sec − 1 1 0.3 0.4 2 × 10 – 3 2 0.6 0.8 8 × 10 – 3 3 0.6 0.4 4 × 10 – 3
Options
- AR = k A 2 B 1
- BR = k A B
- CR = k A 1 B 0
- DR = k A B - 1
Correct answer
B. R = k A B
Step-by-step solution
Rate   R = k A m B n From Exp. (i) R 1 = 2 × 1 0 – 3 = k 0.3 m 0.4 n From Exp. (ii) R 2 = 8 × 1 0 – 3 = k 0.6 m 0.8 n From Exp. (iii) R 3 = 4 × 1 0 – 3 = k [ 0.6 ] m [ 0.4 ] n R 3 R 1 ⇒ 4 × 1 0 – 3 2 × 1 0 – 3 = k [ 0.6 ] m [ 0.4 ] n k [ 0.3 ] m [ 0.4 ] n 2 ′ = 2 m ∴ m = 1 R 2 R 3 ⇒ 8 × 1 0 – 3 4 × 1 0 – 3 = k [ 0.6 ] m [ 0.8 ] n k [ 0.6 ] m [ 0.4 ] n 2 = 2 n ∴ n = 1 ∴ Rate   law R = k A B