Consider the exothermic equilibrium system below.
The [CuCl4]–2(aq) ion is light green while the [CuBr4]2(aq) ion is dark brown. Originally the equilibrium below was a dark green.

[CuCl4]–2(aq) + 4 Br–(aq) ⇋ [CuBr4]–2(aq) + 4 Cl–(aq)

Predict the color of the solution after the system has re-established equilibrium.

a. Adding a small amount of white NaBr(s).
b. Adding a few drops of Ag+(aq) solution (Ag+ reacts with Cl– ions).

Can someone explain this to me please and show me how you got the answer?

Respuesta :

Answer:

a) dark brown

b) dark brown

Explanation:

In case (a) the addition of more reactants (bromide ion) favours the forward reaction which leads to the formation of the dark brown complex. According to Le Chatelier's principle, addition of reactants favours the forward reaction.

In case (b) addition of silver ions removes the chloride ion, a product. This favours the forward reaction and more of the dark brown complex is formed according to Le Chatelier's principle.