Surekha was very upset as her silver jewellary had turned black; and lost its lustre. Her father is a science
teacher and he washed cleaned the jewellary using toothpaste and brought the shine back.
a) Why does the silver jewellary tarnishes when left open?
b) How had the toothpaste got the shine of silver back?
c) What value of Surekha's father is seen in this act?
Answers
Answer:
a.)Generally, compounds containing sulfur in the air are naturally occurring which means that sterling jewelry left unattended in the open air will tarnish naturally to a dark color.Silver becomes black because of hydrogen sulfide (sulfur), a substance that occurs in the air. When silver comes into contact with it, a chemical reaction takes place and a black layer is formed. Silver oxidizes faster in places with a lot of light and high humidity.
b.)As toothpastes consist of several abrasive substances (like, Aluminium hydroxide), this layer of silver sulphide can be removed by rubbing the article with toothpaste. This reaction leaves the silver metal all shiny.
c.)THE VALUE THAT IS SEEN IS THAT HIS APPLICATION SKILLS OF HIS STUDY IN REAL LIFE!