chemical science vs law of multiple proportions

chemical science and law of multiple proportions both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemical science	Yes	No	No	No
law of multiple proportions	Yes	No	No	No

chemical science (noun)	law of multiple proportions (noun)
the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions	(chemistry) law stating that when two elements can combine to form more than one compound the amounts of one of them that combines with a fixed amount of the other will exhibit a simple multiple relation