heedfulness vs mindless

heedfulness is a noun but mindless is not a noun.

Word	Noun	Adjective	Verb	Adverb
heedfulness	Yes	No	No	No
mindless	No	Yes	No	No

heedfulness (noun)	mindless (noun)
the trait of staying aware of (paying close attention to) your responsibilities

heedfulness (adjective)	mindless (adjective)
	not mindful or attentive
	devoid of intelligence or thought
	lacking the thinking capacity characteristic of a conscious being
	requiring little mental effort
	not marked by the use of reason