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Question
Give two examples of amphoteric oxides.
Solution
- Aluminium oxide (Al2O3) and zinc oxide (ZnO) are examples of amphoteric oxides.
- The following reactions show the amphoteric character of zinc oxide:
- \[\ce{\underset{(Basic nature)}{ZnO_{(s)}} + 2HCl_{(aq)} -> \underset{Zinc chloride}{ZnCl2_{(aq)}} + H2O_{(l)}}\]
- \[\ce{\underset{(Acidic nature)}{ZnO_{(s)} + 2Na}OH_{(aq)} -> \underset{Sodium zincate}{Na2ZnO2_{(aq)}} + H2O_{(l)}}\]
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