Answer:
A. H3O+/OH−
Explanation:
A conjugate acid-base pair are a pair of molecules that differ in 1 H⁺
A. The conjugate pair of H₃O⁺ = H₂O not OH⁻
B. The conjugate pair of NH₄⁺ is NH₃
C. The conjugate pair of C₂H₃O₂⁻ is HC₂H₃O₂
D. The conjugate pair of H₂SO₃ is HSO₃⁻
That means right option, that is not a conjugate acid-base pair, is:
A. H3O+/OH−
