[sk2012]

Hi

aluminium oxide has amphoteric nature. So, when it is added to a nitrate ( aluminium nitrate) to decreases the acidity of the solution or the combination has less acidic nature. But when we add an acid ( small volume of acid 10 microliter, strong or weak acid) to the solution of nitrate and oxide will it still be able to behave as ampotheric material and prevent the pH from going down or becoming acid since we added acid. I want to understand if the amphoterism is present even after multiple treatments with acid. Here in this situation first by aluminium nitrate followed by another acid.

Your feedback is greatly appreciated

Thank you
SK

[ajkoer]

In the presence of NaOH, the amphoteric Al(OH)3 dissolves. One could view this as a weak acid (HAlO2) reacting with a strong base, forming Sodium Aluminate (variously written as NaAlO2 or NaAl(OH)3).

Interestingly, treating aqueous NaAl(OH)3 with even a mild acid, like CO2, produces an Al(OH)3 precipitate and NaHCO3.