A precipitate is expected when an aqueous solution of rubidium iodide is added to an aqueous solution of?

Aqueous solution of RbI (rubidium iodide) contains Rb⁺ and I⁻ ions.

Aqueous solution of Na₂SO₄ (sodium sulfate) contains Na⁺ and SO₄²⁻ ions. Both NaI and Rb₂SO₄ are soluble in water. Therefore, no precipitate is formed when an aqueous solution of RbI is added to an aqueous solution of Na₂SO₄.

Aqueous solution of FeCl₂ (iron(II) chloride) contains Fe²⁺ and Cl⁻ ions. Both FeI₂ and RbCl are soluble in water. Therefore, no precipitate is formed when an aqueous solution of RbI is added to an aqueous solution of FeCl₂.

Aqueous solution of Ca(NO₃)₂ (calcium nitrate) contains Ca²⁺ and NO₃⁻ ions. Both CaI₂ and RbNO₃ are soluble in water. Therefore, no precipitate is formed when an aqueous solution of RbI is added to an aqueous solution of Ca(NO₃)₂.

Aqueous solution of Ba(OH)₂ (barium hydroxide) contains Ba²⁺ and OH⁻ ions. Both BaI₂ and RbOH are soluble in water. Therefore, no precipitate is formed when an aqueous solution of RbI is added to an aqueous solution of Ba(OH)₂.

Aqueous solution of Pb(ClO₃)₂ (lead perchlorate) contains Pb²⁺ and ClO₄⁻ ions. PbI₂ is insoluble in water, while RbClO₄ is soluble. Therefore, PbI₂(aq) precipitate is formed when an aqueous solution of RbI is added to an aqueous solution of Ca(NO₃)₂.
Pb²⁺(aq) + 2I⁻(aq) → PbI₂(s)

...... The answer is : lead perchlorate

lead perchlorate