technical-grade vs chemical science

technical-grade is not a noun while chemical science is a noun.

Word	Noun	Adjective	Verb	Adverb
technical-grade	No	Yes	No	No
chemical science	Yes	No	No	No

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

technical-grade (adjective)	chemical science (adjective)
containing small amounts of other chemicals, hence slightly impure