How does the equilibrium change to counter the removal of a in this reaction? a + b ⇌ ab the equilibrium . simultaneously, there’s an increase in the reaction.

Based on Le Chatelier's principle, if the equilibrium of a system is disturbed by changing the temperature, pressure or concentration, then it will shift in a direction to undo the effect of the induced change.

The given equilibrium is:

A + B ↔ AB

Removal of the reactant A implies that the concentration of A has decreased, therefore the equilibrium will shift in a direction to produce more of A. Thus, it will shift to the left and the rate of the reverse or backward reaction will increase.

AnsweR

The equilibrium SHIFTS LEFT. Simultaneously, there’s an increase in the REVERSE reaction.

Explanation:

A + B ⇌ AB

increased stability in the completion of fluorine's outer shell.