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Anita bought silver jewellery along with her friend Rita. Anita advised Rita to make sure that the jewellery was kept in a sealed box

Monjur Alahi

Anita bought silver jewellery along with her friend Rita. Anita advised Rita to make sure that the jewellery was kept in a sealed box and not exposed to air, but Rita forgot and left it open. After some months when Rita decided to wear it, she found the jewellery was all black. Rita was very upset.

(a) Why did the jewellery become black when exposed to air ?

(b) What is this process called ?


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1 Answers

Salim Ahmed Kawsar

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(a) Silver becomes black when exposed to air to form a coating of silver sulphide.

(b) The process called is as corrosion.

(c) Awareness, intelligence, Sharing, Co-operative.

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