Not sure about rubidum, but rubidium is a metal.
Zodarion rubidum was created in 1914.
This alkali metal is Rubidium Rb, having atomic no 37
37
non-metal
non-metal
Non metal
non metal
A non-metal.
Oxygen is a non-metal. It is a reactive gas that is essential for sustaining life and is found in the non-metal group on the periodic table.
Sodium chloride is a compound, not a chemical element.
Neon is a non-metal. It is one of the Noble Gasses which are all non-metals.
some paper is. but its mostly made out of plastic from fish guts.