Question

Which of the following oxides are amphoteric? This question has multiple correct options
(A) \[BeO\]
(B) \[SnO\]
(C) \[\;ZnO\]
(D) \[A{l_2}{0_3}\]

Answer 1

Hint: Amphoteric oxides are oxides that react both as an acid and as a base. Many metals such as copper, zinc, aluminum, tin, lead, and beryllium form amphoteric oxides or hydroxides.

Complete step by step answer:
Aluminum oxide, beryllium oxide, tin oxide, zinc oxide all are amphoteric. They have reactions as both a base and an acid. The oxide ions are held too strongly in the solid lattice to react with the water.
Aluminum oxide contains oxide ions, and thus reacts with acids in the same way sodium or magnesium oxides do.It acts as an acid with the base, and a base with an acid, neutralizing the other and producing a salt.
\[SnO\]reacts with strong acid to give tin(II) salts and in the reaction with strong base \[SnO\] givesstannites containing \[Sn{\left( {OH} \right)_3}^ - \]
Therefore,amphoteric oxides are \[BeO\], \[SnO\], \[\;ZnO\], \[A{l_2}{0_3}\]

So, the correct options are A, B, C, D.

Note: Aluminum reacts with hydrochloric acid as well as sodium hydroxide solution to produce hydrogen gas.
Further, the equations are shown below, \[Al(s) + 6HCl(aq) \to 2AlC{l_3}(aq) + \,3{H_2}(g)\]
\[Al(s) + 2NaOH(aq) + 2{H_2}O(l) \to \ ,2NaAl{O_2}(aq) + {H_2}(aq)\]
Copperalso reacts with dil HCl and produces hydrogen and it also reacts with NaOH.
The equations are as shown below,
\[Cu(s) + 2HCl(aq) \to CuC{l_2}(aq) + \,{H_2}(g)\]
\[Cu(s) + 2NaOH(aq) \to Cu{\left( {OH} \right)_2}(aq) + \,2Na(s)\]