sourness vs sulkiness

sourness and sulkiness both are nouns.

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

As nouns, sourness and sulkiness are synonyms defined as:

Other synonyms of sourness include moroseness, sullenness.

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