Question

Which of the following compounds is more soluble in acidic solution than in pure neutral water?

Answer 1

Answer:

The compound A (BaCO₃) is the most soluble in acidic solution.

Explanation:

We analyze the dissociation of the compounds:

A) BaCO₃ ⇒ Ba⁺² + CO₃⁻²

CO₃⁻² is the conjugated base of HCO₃ acid, which is a weak acid, therefore its conjugate base is strong.

B) CuI ⇒ Cu⁺ + I⁻

I⁻ is the conjugated base of HI acid, which is a strong acid, therefore its conjugate base is weak.

C) PbCl₂ ⇒ Pb⁺² + 2 Cl⁻

Cl⁻ is the conjugated base of HCl acid, which is a strong acid, therefore its conjugate base is weak.

D) AgBr ⇒ Ag⁺ + Br⁻

Br⁻ is the conjugated base of HBr acid, which is a strong acid, therefore its conjugate base is weak.

E) NH₄NO₃ ⇒ NH₄⁺ + NO₃⁻

NO₃⁻ is the conjugated base of HNO₃ acid, which is a strong acid, therefore its conjugate base is weak.

As the medium is acidic, there is a high concentration of H₃O⁺ and the CO₃⁻² is a strong base, the concentration of CO₃⁻² decreases to form H₂CO₃ and by the Le Chatelier's principle the equilibrium of the dissociation reaction shifts to the right and increases the solubility of the salt.