acid vs sulphurous

acid is a noun but sulphurous is not a noun.

Word	Noun	Adjective	Verb	Adverb
acid	Yes	Yes	No	No
sulphurous	No	Yes	No	No

As adjectives, acid and sulphurous are synonyms defined as:

Other synonyms of acid include acerb, acerbic, acrid, bitter, blistering, caustic, sulfurous, virulent, vitriolic.

acid (noun)	sulphurous (noun)
street name for lysergic acid diethylamide
any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt

acid (adjective)	sulphurous (adjective)
having the characteristics of an acid	of or related to or containing sulfur or derived from sulfur
being sour to the taste	characterized by oppressive heat and humidity
harsh or corrosive in tone	harsh or corrosive in tone