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Question
Why zinc and aluminium are considered to have a unique nature. Give balanced equations to support your answer.
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Solution
They react with acids and can even react with hot concentrated alkalis to form hydrogen and soluble salt.
Zn + 2NaOH → Na2ZnO2 + H2
2Al + 6NaOH→ 2Na2Al O3 + 3H2
Oxides and hydroxides of zinc and aluminum are amphoteric. They react with both bases and acids to give salt and water.
ZnO + 2HCl → ZnCl2 + H2O
ZnO + 2NaOH →Na2ZnO2 + H2O
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