A silver mirror was installed on the wall of the bathroom decoration, and now the silver mirror is reddish. What is the reason? Is it the quality of the mirror?

The mirror materials, silver or aluminum and mercury, are toxic and have not been used for a long time. Silver is coated by chemical "silver mirror reaction". Add glucose water to the ammonia solution of silver nitrate, and glucose will reduce the invisible silver ions into silver particles, which will be deposited on the glass to make a silver mirror, and finally a layer of paint will do. In recent years, many mirrors in department stores have been aluminized on the back. Aluminum is a silvery and shiny metal, which is much cheaper than precious silver. Aluminum mirror is made by evaporating aluminum in vacuum, and aluminum vapor condenses on the glass surface to form a thin aluminum film. The chemical reaction between air and other substances, I have only studied physics for one year, but I haven't taught it yet.