sulkiness vs sourness

sulkiness and sourness both are nouns.

Word	Noun	Adjective	Verb	Adverb
sulkiness	Yes	No	No	No
sourness	Yes	No	No	No

As nouns, sulkiness and sourness are synonyms defined as:

Other synonyms of sulkiness include moroseness, sullenness.

sulkiness (noun)	sourness (noun)
a sullen moody resentful disposition	the property of being acidic
a feeling of sulky resentment	a sullen moody resentful disposition
a mood or display of sullen aloofness or withdrawal	the taste experience when vinegar or lemon juice is taken into the mouth