chain of mountains vs Saint Elias Mountains

chain of mountains and Saint Elias Mountains both are nouns.

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

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