chemical science vs reaction

chemical science and reaction both are nouns.

Word	Noun	Adjective	Verb	Adverb
chemical science	Yes	No	No	No
reaction	Yes	No	No	No

chemical science (noun)	reaction (noun)
the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions	a bodily process occurring due to the effect of some antecedent stimulus or agent
	doing something in opposition to another way of doing it that you don't like
	an idea evoked by some experience
	extreme conservatism in political or social matters
	(mechanics) the equal and opposite force that is produced when any force is applied to a body
	a response that reveals a person's feelings or attitude
	(chemistry) a process in which one or more substances are changed into others