Russia vs Russian capital

Russia and Russian capital both are nouns.

Word	Noun	Adjective	Verb	Adverb
Russia	Yes	No	No	No
Russian capital	Yes	No	No	No

Russia (noun)	Russian capital (noun)
a former communist country in eastern Europe and northern Asia; established in 1922; included Russia and 14 other soviet socialist republics (Ukraine and Byelorussia and others); officially dissolved 31 December 1991	a city of central European Russia; formerly capital of both the Soviet Union and Soviet Russia; since 1991 the capital of the Russian Federation
formerly the largest Soviet Socialist Republic in the USSR occupying eastern Europe and northern Asia
a former empire in eastern Europe and northern Asia created in the 14th century with Moscow as the capital; powerful in the 17th and 18th centuries under Peter the Great and Catherine the Great when Saint Petersburg was the capital; overthrown by revolution in 1917
a federation in northeastern Europe and northern Asia; formerly Soviet Russia; since 1991 an independent state