JEE Main20254 Apr 2025Morning ShiftChemistryChemical KineticsActual
For A ₂+ B ₂ 2 AB E _ a for forward and backward reaction are 180 and 200 ~kJ ~mol ⁻¹ respectively If catalyst lowers E _ a for both reaction by 100 ~kJ ~mol ⁻¹ . Which of the following statement is correct?
Options
- ACatalyst does not alter the Gibbs energy change of a reaction.
- BCatalyst can cause non-spontaneous reactions to occur.
- CThe enthalpy change for the reaction is +20 ~kJ ~mol ⁻¹ .
- DThe enthalpy change for the catalysed reaction is different from that of uncatalysed reaction.
Correct answer
A. Catalyst does not alter the Gibbs energy change of a reaction.
Step-by-step solution
A ₂+ B ₂ 2 AB E _ f =180 ~kJ ~mol ⁻¹ E _ b =200 ~kJ ~mol ⁻¹ H = E _ f - E _ b =-20 ~kJ ~mol ⁻¹ In presence of catalyst : aligned & E _ f =180-100=80 ~kJ ~mol ⁻¹ & E _ b =200-100=100 ~kJ ~mol ⁻¹ aligned Catalyst does not change H or G of a reaction.