The metals that easily tarnish when exposed in air are belongs in the Group A1 (except for Hydrogen) of periodical table, they are:
Lithium (Li)
Sodium (Na)
Potassium (K)
Rubidium (Rb)
Cesium (Cs)
Francium (Fr)
Those are alkali metals, a highly reactive metals with characteristics of shiny, soft, low-melting and boiling point that tarnish easily when expose to air and water.
Do you mean skin? Some it says 925 but it's silver platted. Same with some gold. Copper just breaks in half. I think it's more temputer then anything. Also skin type form diets I assume.
When exposed to air, the alkali metals tarnish easily. This is because they react with oxygen, moisture and carbon dioxide in the air to produce oxides, hydroxides and carbonates. But above all, silver and copper gets tarnished most when exposed to air.
The metals known as alkali metals are instantly tarnished when they are exposes to air. All the elements of group 1A are alkali metals except hydrogen. They are:
Metals that are instantly tarnished when exposed to air include copper, silver, and brass. These metals contain high levels of sulfur, which reacts with oxygen in the air to form a black or green coating called tarnish. Other metals, such as gold and platinum, are not easily tarnished because they do not react with oxygen.
copper, silver, and brass. These metals contain high levels of sulfur, which reacts with oxygen in the air to form a black or green coating called tarnish. Other metals, such as gold and platinum, are not easily tarnished because they do not react with oxygen.
they react with oxygen, moisture and carbon dioxide in the air to produce oxides, hydroxides and carbonates. But above all, silver and copper gets tarnished most when exposed to air.