For the reaction: 3A → 2B, the following graph is obtained experimentally. The rate of reaction when — Chemical Kinetics Chemistry Question

💡 Solution & Explanation

The plot of [A]^-3 vs t is linear, so n-1 = 3 => order n = 4. Integrating -d[A]/dt = k'[A]^4 gives 1/(3[A]^3) = k't + C. Slope = 3k' = 1 => k' = 1/3. Rate of reaction is defined as (-1/3)d[A]/dt = (1/3) * (1/3)[A]^4 = 1/9 [A]^4. At [A]=0.2, rate = 1/9 * (0.2)^4 = 16/9 × 10^-4. Therefore, correct answer is B.