Question

g, Assuming the precipitate is totally insoluble in water, which aqueous ions will be present in the solution (collected in the beaker) after the equivalence point (after the limiting reagent is used up)? Question 4 options: 1) Cl1- (aq) 2) Na1+ (aq) 3) OH1- (aq) 4) Cu2+ (aq)

Answer 1

Answer:

Cl⁻, Na⁺, OH⁻

Explanation:

The titration is:

CuCl₂(aq) + 2 NaOH(aq) → Cu(OH)₂(s) + 2 NaCl(aq)

In solution, before the reaction, the ions are Cu²⁺ and Cl⁻. The addition of NaOH (Na⁺ + OH⁻) produce the precipitation of Cu²⁺ forming Cu(OH)₂(s). When you reach the equivalence point, there is no Cu²⁺ because precipitates completely. All OH⁻ ions reacts when are added but when Cu²⁺ is finished, excess OH⁻ ions still in solution helping to detect the equivalence point.

Thus, ions present after the equivalence point are: Cl⁻, Na⁺ (Don't react, spectator ions), and OH⁻.