GKFix MCQ Question

Why is carbonic acid's Ka2 much smaller than its Ka1?

• A. H₂CO₃ decomposes into CO₂ and H₂O
• B. Ka2 refers to reverse reaction only
• C. CO₃²⁻ is highly unstable
• D. The second proton must be removed from a negatively charged HCO₃⁻ ion