radium vs atomic number 88

radium and atomic number 88 both are nouns.

Word	Noun	Adjective	Verb	Adverb
radium	Yes	No	No	No
atomic number 88	Yes	No	No	No

As nouns, radium and atomic number 88 are synonyms defined as:

radium and atomic number 88: an intensely radioactive metallic element that occurs in minute amounts in uranium ores

Other synonyms of radium include Ra.

radium (noun)	atomic number 88 (noun)
an intensely radioactive metallic element that occurs in minute amounts in uranium ores	an intensely radioactive metallic element that occurs in minute amounts in uranium ores