Subjective Type

Answer the following: (a) Aluminium is a more active metal than iron, but suffers less corrosion. Why? (b) Explain and give reasons why aluminium vessels should not be cleaned with powders containing alkalis.

Solution

(a) Aluminium is more active metal but it gets oxidized and forms a thin protective layer on its surface which prevents further corrosion.
(b) Aluminium vessels should not be cleaned with powders containing alkalis because it results in the formation of meta aluminates and hydrogen.

$$ 2Al + 2NaOH + 2H_{2}O \rightarrow 2NaAlO_{2} + 3H_{2}$$

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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Metals and Non - metals

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