Give reasons:
(a) Metals like $Na, K, Ca$ and $Mg$ are never found in their free state in nature.
(b) Iron loses its lustre over time whereas gold does not.

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Solution

(a) These metals are highly reactive and thus readily react with air and water to form their compounds.
(b) Iron moderatley reacts with air to form its oxide. The oxide forms a layer over the iron metal. Hence it loses its lustre over time. Gold being quiet unreactive metal does not react with air easily and hence retains its shine.

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Question 61
Explain the following:

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Give reasons: (a) Metals like Na, K, Ca and Mg are never found in their free state in nature. (b) Iron loses its lustre over time whereas gold does not.

Give reasons:
(a) Metals like $Na, K, Ca$ and $Mg$ are never found in their free state in nature.
(b) Iron loses its lustre over time whereas gold does not.