Given: A1=A2, Ea1=Ea2+20 kJ/mol, T = 300 K, R = 8.3 J K⁻¹ mol⁻¹
Using Arrhenius equation: k=Ae−Ea/RT
k1k2=e−Ea1/RTe−Ea2/RT=e(Ea1−Ea2)/RT
Ea1−Ea2=20 kJ/mol = 20000 J/mol
k1k2=e8.3×30020000=e249020000
lnk1k2=249020000=8.03≈8
JEE Main 2026 — Chemistry Physical Chemistry
Pre-exponential factors of two different reactions of same order are identical. Let activation energy of first reaction exceeds the activation energy of second reaction by 20 kJ mol−1. If k1 and k2 are the rate constants of first and second reaction respectively at 300 K, then lnk1k2 will be ____. (nearest integer) [R=8.3 J K−1 mol−1]
Held on 21 Jan 2026 · Verified 6 Jul 2026.
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