adequateness vs adequacy

adequateness and adequacy both are nouns.

Word	Noun	Adjective	Verb	Adverb
adequateness	Yes	No	No	No
adequacy	Yes	No	No	No

As nouns, adequateness and adequacy are synonyms defined as:

adequateness and adequacy: the quality of being able to meet a need satisfactorily:

adequateness (noun)	adequacy (noun)
the quality of being able to meet a need satisfactorily:	the quality of being able to meet a need satisfactorily:
	the quality of being sufficient for the end in view