arsenic trioxide vs arsenous oxide

arsenic trioxide and arsenous oxide both are nouns.

Word	Noun	Adjective	Verb	Adverb
arsenic trioxide	Yes	No	No	No
arsenous oxide	Yes	No	No	No

As nouns, arsenic trioxide and arsenous oxide are synonyms defined as:

arsenic trioxide and arsenous oxide: a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer

Other synonyms of arsenic trioxide include arsenic, arsenous anhydride, ratsbane, white arsenic.

arsenic trioxide (noun)	arsenous oxide (noun)
a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer	a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer