national capital vs Salvadoran capital

national capital and Salvadoran capital both are nouns.

Word	Noun	Adjective	Verb	Adverb
national capital	Yes	No	No	No
Salvadoran capital	Yes	No	No	No

national capital (noun)	Salvadoran capital (noun)
the capital city of a nation	the capital and largest city of El Salvador; has suffered from recurrent earthquakes