Question

why do metals lose their lusture when exposed to the air?​

Answer 1

Explanation:

The metals lose their shine on brightness on keeping in air for a long time due to formation of a thin layer of oxide, carbonate or sulphide on their surface by the slow action of various gases present in air.

Answer 2

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The metals lose their shine on brightness on keeping in air for a long time due to formation of a thin layer of oxide, carbonate or sulphide on their surface by the slow action of various gases present in air.

Metals when exposed to air and moisture lose their lusture due to the formation of their compunds.

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