Question

In the equilibrium reaction: $A+B\rightleftharpoons AB+heat$ (in a closed container), which of the following could increase the forward reaction rate?
I. Increasing the concentration of $AB$.
II. Increasing the concentration of $A$.
III. Removing some of product $AB$.

• A. I only
• B. III only
• C. I and III only
• D. II and III only
• E. I, II and III

Answer 1

The correct option is D II and III only

In the equilibrium reaction: $A+B\rightleftharpoons AB+$ heat (in a closed container), the forward reaction rate can be increased by, II and III only.
II. Increasing the concentration of $A$
III. Removing some of the product $AB$
In above cases, more and more $A$ will react with $B$ to form more and more $B$.
The equilibrium will shift in the forward direction. This is according to LeChatelier's principle.
Note:
I. Increasing the concentration of $AB$.
The equilibrium will shift in the reverse direction. More and more of AB will decompose to give $A$ and $B$.