Hello!
When aqueous solutions of Li₂SO₄ and NaI are mixed the following reaction occurs:
Li₂SO₄(aq) + 2NaI(aq) → 2LiI(aq) + Na₂SO₄(aq)
The compounds produced from this reaction are all soluble, so no precipitate is formed. We know that those compounds (LiI and Na₂SO₄) are soluble because of the solubility rules which states that salts from Group I elements (Li⁺, Na⁺) are soluble.
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