chromatograph vs apparatus

chromatograph and apparatus both are nouns.

Word	Noun	Adjective	Verb	Adverb
chromatograph	Yes	No	No	No
apparatus	Yes	No	No	No

As nouns, apparatus is a hypernym of chromatograph; that is, apparatus is a word with a broader meaning than chromatograph:

chromatograph: equipment that enables a sophisticated separation, e.g. gas chromatographic or liquid chromatographic separation.
apparatus: equipment designed to serve a specific function

Other hypernyms of chromatograph include setup.

chromatograph (noun)	apparatus (noun)
equipment that enables a sophisticated separation, e.g. gas chromatographic or liquid chromatographic separation.	equipment designed to serve a specific function
	(anatomy) a group of body parts that work together to perform a given function