Question

The reason for tarnishing of silver is………..?

Answer 1

Hint : Metals are highly reactive as they can easily lose their outermost electron to form ion and react. Due to this reason metals when exposed to air which contain almost all the gases, the metal forms compounds with the gases depending on their properties. The formation of unwanted compounds on metal surfaces lowers their reactivity.

Complete Step By Step Answer:
Tarnishing is the word which generally means a fine layer of corrosion on a metal surface. Due to formation of an unexpected compound.
Silver tarnishing happens due to the formation of silver sulfide on its surface which turns the color of silver to darkens. Tarnishing is a gradual process; it can also happen with oxygen when silver is exposed too much.
$Ag + {O_2} + {H_2}S \to A{g_2}O + A{g_2}S$
Oxygen and hydrogen sulfide are present in the air. Thus formation of $A{g_2}O + A{g_2}S$ causes tarnishing.
To avoid tarnishing and keeping up the shine of silver items they must be cleaned with soap water and solution of ammonia. Silver items must be kept in cool places to avoid sunlight, pollution and chemical exposure like perfumes and air sprays.
Thus the reason for tarnishing silver can be exposure to air.

Note :
Silver due to it’s high malleability and ductility are used in varieties of ornaments, utensils, watches and even silver is applied on sweets.