Hl gas is added to the system at equilibrium below. How does the system adjust to reestablish equilibrium?

[tex]\[51.8 \text{ kJ} + H_2(g) + I_2(g) \rightleftharpoons 2 HI(g)\][/tex]

A. The reaction shifts to the left (reactants) and the concentrations of [tex]\(H_2\)[/tex] and [tex]\(I_2\)[/tex] decrease.

B. The reaction shifts to the right (products) and the concentrations of [tex]\(I_2\)[/tex] and [tex]\(H_2\)[/tex] increase.

C. The reaction shifts to the left (reactants) and the concentrations of [tex]\(H_2\)[/tex] and [tex]\(I_2\)[/tex] increase.

D. The reaction shifts to the right (products) and the concentrations of [tex]\(H_2\)[/tex] and [tex]\(I_2\)[/tex] decrease.



Answer :

To determine how the system adjusts to re-establish equilibrium when [tex]\( HI \)[/tex] gas is added, we must consider Le Chatelier's Principle. Le Chatelier's Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change.

The given reaction is:

[tex]\[ 51.8 \, \text{kJ} + H_2(g) + I_2(g) \rightleftharpoons 2 HI(g) \][/tex]

With the addition of [tex]\( HI \)[/tex] gas, we are increasing the concentration of one of the products in the equilibrium system. According to Le Chatelier's Principle, the system will adjust to reduce the increased concentration of [tex]\( HI \)[/tex].

1. To reduce the concentration of [tex]\( HI \)[/tex], the system will shift the equilibrium position to the left, towards the reactants.
2. As the equilibrium shifts to the left, the quantities of [tex]\( H_2 \)[/tex] and [tex]\( I_2 \)[/tex] will increase to form more [tex]\( H_2 \)[/tex] and [tex]\( I_2 \)[/tex] while the amount of [tex]\( HI \)[/tex] will decrease.

Therefore, the correct adjustment:

- The reaction shifts to the left (towards the reactants).
- The concentrations of [tex]\( H_2 \)[/tex] and [tex]\( I_2 \)[/tex] will increase.

So, the correct answer is:

"The reaction shifts to the left (reactants) and the concentrations of [tex]\( H_2 \)[/tex] and [tex]\( I_2 \)[/tex] increase."