responsive vs responsiveness

responsive is not a noun while responsiveness is a noun.

Word	Noun	Adjective	Verb	Adverb
responsive	No	Yes	No	No
responsiveness	Yes	No	No	No

responsive (noun)	responsiveness (noun)
	the quality of being responsive; reacting quickly; as a quality of people, it involves responding with emotion to people and events
	responsive to stimulation

responsive (adjective)	responsiveness (adjective)
readily reacting or replying to people or events or stimuli; showing emotion
containing or using responses; alternating
reacting to a stimulus