Verified Solution • 2025–26 Session moderate

QJEEM07Ch42cf: JEE Main 2007 Chemistry - Class 12 JEEM07Ch42cf Solution: The energies of activation for forward and reverse reactions…

The energies of activation for forward and reverse reactions for A2 + B2 ⇋ 2AB are 180 kJ mol−1 and 200 kJ mol−1 respectively. The presence of catalyst lowers the activation energy of both (forward and reverse) reactions by 100 kJ mol−1. The enthalpy change of the reaction ( A2 + B2 → 2AB) in the presence of catalyst will be (in kJ mol−1)

Multiple Choice Options

  • A 300
  • B 120
  • C 200
  • D 20

Step-by-Step Verified Solution

ΔHR=Ef−Eb=180−200=−20kJ/mol

The nearest correct answer given in choices may be obtained by neglecting sign.

Related Learning Resources & Exam Preparation