Question

Which is more acidic BeO or B2O3

Answer 1

B203 is an anhydride because when it reacts with water, it gives​ boric acid of boric acid Due to this B2O3 is acidic while in case of Al2O3 when it react with both acids and bases, such as hydrofluoric acid and sodium hydroxide, acting as an acid with a base and a base with an acid, neutralising the other and producing a salt.  Thus B203 is acidic and Al203 is amphoteric

Answer 2

B203 is an anhydride because when it reacts with water, it gives​ boric acid of boric acid due to this B2O3 is more acidic.  Hope it helps....