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Consider the following transformation involving first order elementary reaction in each step at constant temperature as shown below. A+B underset…

JEE Main 2024 — Chemistry Physical Chemistry

2024integerhard

Consider the following transformation involving first order elementary reaction in each step at constant temperature as shown below. A+B Step 1 Step 3 C→ Step 2 PA+B \underset{\text { Step 3 }}{\text { Step } 1} C \xrightarrow{\text { Step 2 }} PA+B Step 3  Step 1​C Step 2 ​P Some details of the above reactions are listed below.  Step  Rate constant (sec−1) Activation energy (kJ mol−1)1k13002k22003k3Ea3\begin{array}{ccc} \text { Step } & \text { Rate constant }\left(\mathbf{s e c}^{-\mathbf{1}}\right) & \text { Activation energy }\left(\mathbf{k J ~ m o l}^{-\mathbf{1}}\right) \\ 1 & \mathrm{k}_1 & 300 \\ 2 & \mathrm{k}_2 & 200 \\ 3 & \mathrm{k}_3 & \mathrm{Ea}_3 \end{array} Step 123​ Rate constant (sec−1)k1​k2​k3​​ Activation energy (kJ mol−1)300200Ea3​​ If the overall rate constant of the above transformation (k)(k)(k) is given as k=k1k2k3k=\frac{k_1 k_2}{k_3}k=k3​k1​k2​​ and the overall activation energy (Ea)\left(\mathrm{E}_{\mathrm{a}}\right)(Ea​) is 400 kJ mol−1400 \mathrm{~kJ} \mathrm{~mol}^{-1}400 kJ mol−1, then the value of Ea3\mathrm{Ea}_3Ea3​ is \qquad kJmol−1\mathrm{kJ} \mathrm{mol}^{-1}kJmol−1 (nearest integer)

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