chemical science vs reverse osmosis

chemical science and reverse osmosis both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemical science	Yes	No	No	No
reverse osmosis	Yes	No	No	No

chemical science (noun)	reverse osmosis (noun)
the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions	(chemistry) a method of producing pure water; a solvent passes through a semipermeable membrane in a direction opposite to that for natural osmosis when it is subjected to a hydrostatic pressure greater than the osmotic pressure