Question

Many enzymes catalyze both forward and reverse reactions. Which one of the following statement is NOT correct?

• A. An equilibrium is established after some time.
• B. It is possible to control the directions of the reaction by suitably removing the formed product.
• C. These reactions are both temperature and concentration dependent.
• D. The forward and reverse reactions proceed via different activation complexes.

Hint:

In enzyme-catalyzed reversible reactions, both directions share the same activation complex and transition state. Misconceptions often arise when equating different pathways to different mechanisms.

Answer 1

The Correct Option is D

Step 1: Understanding enzyme catalysis. 
Enzymes lower the activation energy of both forward and reverse reactions, facilitating the establishment of equilibrium. They do not alter the position of equilibrium but speed up the attainment of it.
Step 2: Analyze the options.
Option (1) is correct: Reversible enzyme-catalyzed reactions reach equilibrium after some time.
Option (2) is correct: Removing the product shifts the equilibrium, influencing the direction of the reaction (Le Chatelier’s Principle).
Option (3) is correct: Enzymatic activity depends on both temperature and concentration.
Option (4) is incorrect: The forward and reverse reactions proceed via the same transition state (activation complex), not different ones.
Therefore, statement (4) is NOT correct.