Question

Which of the following ions will most likely form a precipitate when reacted with SO₄²⁻?

1. F⁻
2. Na⁺
3. Ba²⁺
4. Rb⁺

Answer 1

Ba^2+ is the ion that will most likely form a precipitate when reacted with SO4^2-, as BaSO4 is insoluble in water and will precipitate out of the solution.

Step-by-step explanation:

Of the listed ions that may react with SO42− to form a precipitate, Ba2+ will most likely form a precipitate. This is because barium sulfate (BaSO4) is known to be insoluble in water. When solutions of barium ions like Ba(NO3)2 and a sulfate source such as sodium sulfate (Na2SO4) are mixed, a precipitation reaction is expected, leading to the formation of insoluble BaSO4 as a solid precipitate. The net ionic equation for this reaction would be Ba2+ (aq) + SO42− (aq) → BaSO4 (s). Sodium chloride (NaCl) and sodium hydroxide (NaOH) would not produce such a reaction since they do not provide the necessary sulfate ion and are highly soluble with barium ions.