impatient vs impatience

impatient is not a noun while impatience is a noun.

Word	Noun	Adjective	Verb	Adverb
impatient	No	Yes	No	No
impatience	Yes	No	No	No

impatient (noun)	impatience (noun)
	a dislike of anything that causes delay
	a restless desire for change and excitement
	a lack of patience; irritation with anything that causes delay

impatient (adjective)	impatience (adjective)
restless or short-tempered under delay or opposition
(usually followed by `to') full of eagerness