pentavalent vs chemistry

pentavalent is not a noun while chemistry is a noun.

Word	Noun	Adjective	Verb	Adverb
pentavalent	No	Yes	No	No
chemistry	Yes	No	No	No

pentavalent (noun)	chemistry (noun)
	the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions
	the way two individuals relate to each other
	the chemical composition and properties of a substance or object

pentavalent (adjective)	chemistry (adjective)
having a valence of five