Shashi bought new silver anklets. After a month, she found that the anklets turn black


#1

Shashi bought new silver anklets. After a month, she found that the anklets turn black. She has doubt that it is not of pure silver but her neighbour Rakhi told her that it is of pure silver and advised her to wash it with tamarind or lemon juice to get the lustre back. She followed the advise and get the lustre of her anklets back.
Answer the following questions based on the above passage.
(i) Why these turn black after some time?
(ii) Why the anklets become lustrous on washing with tamarind or lemon juice?
(iii) What values are exhibited by Rakhi?


#2

(i) Anklets turned black due to the reaction of silver with atmospheric H2S, which, results in the formation of black coloured silver sulphide (Ag2S).
(ii) Ag2S dissolves in acids present in tamarind or lemon juice, so the anklets got their lustre back.
(iii) The values exhibited by Rakhi are awareness, helpful, knowledgeable and scientific temperament.