chemical science vs law of reciprocal proportions

chemical science and law of reciprocal proportions both are nouns.

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

chemical science (noun)	law of reciprocal 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 the proportions in which two elements separately combine with a third element are also the proportions in which they combine together