Saint Elias Mountains vs chain of mountains

Saint Elias Mountains and chain of mountains both are nouns.

Word	Noun	Adjective	Verb	Adverb
Saint Elias Mountains	Yes	No	No	No
chain of mountains	Yes	No	No	No

Saint Elias Mountains (noun)	chain of mountains (noun)
a range of mountains between Alaska and the Yukon territory	a series of hills or mountains