receptive vs receptiveness

receptive is not a noun while receptiveness is a noun.

Word	Noun	Adjective	Verb	Adverb
receptive	No	Yes	No	No
receptiveness	Yes	No	No	No

receptive (noun)	receptiveness (noun)
	willingness or readiness to receive (especially impressions or ideas)

receptive (adjective)	receptiveness (adjective)
ready or willing to receive favorably
able to absorb liquid (not repellent)
of a nerve fiber or impulse originating outside and passing toward the central nervous system
open to arguments, ideas, or change