atomic number 80 vs Hg

atomic number 80 and Hg both are nouns.

Word	Noun	Adjective	Verb	Adverb
atomic number 80	Yes	No	No	No
Hg	Yes	No	No	No

As nouns, atomic number 80 and Hg are synonyms defined as:

atomic number 80 and Hg: a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures

Other synonyms of atomic number 80 include hydrargyrum, mercury, quicksilver.

atomic number 80 (noun)	Hg (noun)
a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures	a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures