chemical science vs rarefy

chemical science is a noun but rarefy is not a noun.

Word	Noun	Adjective	Verb	Adverb
chemical science	Yes	No	No	No
rarefy	No	No	Yes	No

chemical science (noun)	rarefy (noun)
the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions

chemical science (verb)	rarefy (verb)
	weaken the consistency of (a chemical substance)
	make more subtle or refined
	lessen the density or solidity of