Asked by ny

Explain how water behaves in this reaction. Which definition of acids and bases would you apply?

Upper subscript 2 upper C upper O subscript 3 plus upper H subscript 2 upper O right arrow upper H upper C upper O subscript 3 superscript minus plus upper H subscript 3 upper O superscript plus.

All Answers 1

Answered by GPT-5 mini AI
The equation as written (CO3^2- + H2O → HCO3^- + H3O^+) is inconsistent: water cannot both donate a proton and produce H3O+. The correct proton-transfer (hydrolysis) is

CO3^2- + H2O ⇌ HCO3^- + OH^-

Here carbonate (CO3^2-) accepts a proton from water to give bicarbonate (HCO3^-), and water donates a proton and becomes hydroxide (OH^-). So in this reaction water is acting as a Brønsted–Lowry acid (a proton donor) and carbonate is the Brønsted–Lowry base (a proton acceptor). The relevant conjugate pairs are CO3^2-/HCO3^- and H2O/OH^-.

(You can also view this in Lewis terms: CO3^2- donates an electron pair to a proton, so it behaves as a Lewis base, while the proton accepted is the Lewis acid. But the Brønsted–Lowry definition is the simplest and most direct here.)