Answer
$HNO_2(aq) + H_2O(l) N{O_2}^-(aq) + H_3O^+(aq)$
Therefore: $HNO_2$ = Acid.
${PO_4}^{3-}(aq) + H_2O(l) {HPO_4}^{2-}(aq) + OH^-(aq)$
Therefore: ${PO_4}^{3-}$ = Base.
$H{CO_3}^-(aq) + H_2O(l) {CO_3}^{2-}(aq) + H_3O^+(aq)$
$H{CO_3}^-(aq) + H_2O(l) H_2{CO_3}(aq) + OH^-(aq)$
Therefore: $H{CO_3}^-$ = Amphiprotic.
Work Step by Step
Remember that acids are molecules that are capable of donating one proton. ($H{CO_3}^-$ and $HNO_2$)
And bases are molecules capable of receiving one proton. ($H{CO_3}^-$ and ${PO_4}^{3-}$)
- Amphiprotic are species that can either receive or donate a proton.
