Mention the uses of Gold (Au).

Explanation

Gold one of the expensive and precious metals.It is used for coinage ,and has been used as standard for monetary systems in some countris.
It is used extensively in jewellery in its alloy form with copper .It is also used in electroplating to cover other metals with a thin layer of gold which are used in watches,artificial limb joints,cheap jewellery,dental fillings and electrical connectors.
Gold nanoparticles are also used for increasing the efficiency of solar cells and also used an catalyts.