acidity vs sourness

acidity and sourness both are nouns.

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

As nouns, acidity and sourness are synonyms defined as:

Other synonyms of acidity include sour.

As nouns, sourness is a hypernym of acidity; that is, sourness is a word with a broader meaning than acidity:

acidity: the taste experience when something acidic is taken into the mouth
sourness: the taste experience when vinegar or lemon juice is taken into the mouth

Other hypernyms of acidity include sour, tartness.

acidity (noun)	sourness (noun)
pH values below 7	the property of being acidic
the property of being acidic	a sullen moody resentful disposition
the taste experience when something acidic is taken into the mouth	the taste experience when vinegar or lemon juice is taken into the mouth