humanity vs mankind

humanity and mankind both are nouns.

Word	Noun	Adjective	Verb	Adverb
humanity	Yes	No	No	No
mankind	Yes	No	No	No

As nouns, humanity and mankind are synonyms defined as:

Other synonyms of humanity include human beings, human race, humankind, humans, man, world.

humanity (noun)	mankind (noun)
all of the living human inhabitants of the earth	all of the living human inhabitants of the earth
the quality of being humane
the quality of being human