Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

An exothermic reaction X $\to$ Y has an activation energy 30 kJ mol$-$1. If energy change $\Delta$E during the reaction is $-$20 kJ, then the activation energy for the reverse reaction in kJ is ___________. (Integer answer)

Answer (integer) 50

Solution

X $\to$ Y <br><br>$\Delta$E = (E<sub>a</sub>)<sub>f</sub> – (E<sub>a</sub>)<sub>b</sub> <br><br>$\Rightarrow$ – 20 = 30 – (E<sub>a</sub>)<sub>b</sub> <br><br>$\Rightarrow$ (E<sub>a</sub>)<sub>b</sub> = 50 kJ

About this question

Subject: Chemistry · Chapter: Thermodynamics · Topic: Zeroth and First Law

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