Question

Which of the following oxides is amphoteric in character ?

• A. $SnO_2$
• B. $SiO_2$
• C. $CO_2$
• D. $CaO$

Answer 1

Answer: (A)

$SnO_2$

Answer 2

A species is amphoteric if it is soluble in acid (behaves as a base) as well as in base (behaves as an acid). $\underset{\text{Basic}}{ {SnO2 }}$ ${ {+ }}$ $\underset{\text{Acid}}{ {4HCl }}$ ${ {-> SnCl4 \,+ \,2H2O}}$ $\underset{\text{Acid}}{ {SnO2 }}$ ${ {+ }}$ $\underset{\text{Base}}{ {NaOH }}$ ${ {-> Na2SnO3 \,+ \,H2O}}$