Explanation:
conjugate acid/base pairs are compounds which differ by the hydrogen ion (H⁺)
The conjugate based is formed when an acid donates a proton.
HSO₄⁻ --> H⁺ + SO₄²⁻
The conjugate base of HSO₄⁻ is SO₄²⁻
The conjugate acid is formed when a base accepts a proton.
HSO₄⁻ + H⁺ --> H₂SO₄
The conjugate acid of HSO₄⁻ is H₂SO₄