Answer:
Explanation:
Solubility is a measure of the ability of a given substance to dissolve in a liquid, that is, it describes the amount of solute that can be dissolved in a specific amount of solvent. This occurs by solvation. Solvation is the process that involves the association of solvent molecules with molecules or ions of a solute. When the ions of a solvent dissolve, they are separated and surrounded by the molecules that form the solvent. The larger the size of the ion, the greater the number of molecules capable of surrounding it, so it is said that the ion is mostly solvated.
For a substance to dissolve in another the polarity of the molecules must be similar. For example, water is a polar compound and easily dissolves polar substances such as acids, hydroxides and inorganic salts and polar organic compounds. Although there are also exceptions. There are highly polar inorganic compounds that are insoluble in water, such as carbonates or sulphides.
Taking into account the aforementioned, the solubility rules were stated. One of these rules mentions that all chlorides (Cl-) are soluble except those of Hg₂²⁺, among others. This means that by adding KCl to the mixture, the compound Hg₂Cl precipitates through the net ionic equation:
Hg₂²⁺ (aq) + Cl⁻ (aq) ⇒ Hg₂Cl (s)
Then the solution is filtered with the precipitate so that no more Hg₂²⁺ is present in the solution.
Another rule of solubility indicates that sulfates (SO₄²⁻) are all soluble except those of Ba²⁺, among others. That is, between the sulfate and Ba²⁺ precipitate should form. But since it is indicated that potassium sulfate is added to the remaining solution without producing precipitate, it is possible to say that the sulfate is actually reacting with Fe²⁺. This, due to the solubility rule, is soluble with sulfate, producing no precipitate. So, since there is no precipitate, there is no net ionic equation. And there should be no Fe + 2 in the solution due to its reaction with sulfate.
Finally, another solubility rule indicates that all carbonates (CO₃²⁻), phosphates (PO₄³⁻), arsenates (As⁺⁵) and chromates (Cr₂O₄²⁻) are insoluble, except those of Group IA and those of NH₄⁺. Then when potassium carbonate is added to the remaining solution, a precipitate is formed, product of the net ionic equation between Ba²⁺ and carbonate:
Ba²⁺ (aq) + CO₃²⁻ (aq) ⇒ BaCO₃ (s)
