sal soda vs soda ash

sal soda and soda ash both are nouns.

Word	Noun	Adjective	Verb	Adverb
sal soda	Yes	No	No	No
soda ash	Yes	No	No	No

As nouns, sal soda and soda ash are synonyms defined as:

sal soda and soda ash: a sodium salt of carbonic acid; used in making soap powders and glass and paper

Other synonyms of sal soda include soda, sodium carbonate, washing soda.

sal soda (noun)	soda ash (noun)
a sodium salt of carbonic acid; used in making soap powders and glass and paper	a sodium salt of carbonic acid; used in making soap powders and glass and paper