What is the relationship between diatomic molecules and diatomic elements? name one example of a diatomic element.

Diatomic molecules are molecules made of two atoms. The atoms can be of the same element (diatomic elements) like in H2, N2, and O2, or of different elements (diatomic compounds) like in HCl, NaCl, and KBr.  

In contrast, monatomic elements consist of single atoms, like Ar, He and Ne.

a plasma is a warm ionized gasoline consisting of approximately equal numbers of definitely charged ions and negatively charged electrons. the characteristics of plasmas are notably unique from the ones of ordinary neutral gases in order that plasmas are considered a awesome "fourth kingdom of remember."