Question

Explain why surface of some metal acquire a dull appearance. when exposed to air for a long time ?​

Answer 1

Explanation:

It is because they react with various gases present in the air like oxygen and carbon dioxide to form metal oxide and metal carbonate.

Hope it will help you

✌️sai

Answer 2

$\huge\underline\mathfrak\red{Answer}$

⚫ Surface o some metals acquires a dull appearance because they react with air or water in the environment to form undesirable compounds (such as Oxides)..This process is called Corrosion.

⚫For example:- Silver tarnishes, Copper develops a green coating, iron loses it's lustre. The corrosion of iron is called Rusting.

⚫The Chemical formula of Rust is = Fe2O3

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