chemistry vs decomposition reaction

chemistry and decomposition reaction both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemistry	Yes	No	No	No
decomposition reaction	Yes	No	No	No

chemistry (noun)	decomposition reaction (noun)
the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions	(chemistry) separation of a substance into two or more substances that may differ from each other and from the original substance
the way two individuals relate to each other
the chemical composition and properties of a substance or object