How would you test for SO₄²⁻ in an aqueous solution? Write the net ionic equation for the reaction.
a) Add BaCl₂, BaSO₄(s) forms
b) Add HCl, SO₄²⁻ reacts to form H₂SO₄
c) Add NaOH, SO₄²⁻ precipitates as Na₂SO₄
d) Add AgNO₃, SO₄²⁻ reacts to form Ag₂SO₄