demand vs exact

demand is a noun but exact is not a noun.

Word	Noun	Adjective	Verb	Adverb
demand	Yes	No	Yes	No
exact	No	Yes	Yes	No

As verbs, demand and exact are synonyms defined as:

As verbs, exact is a hyponym of demand; that is, exact is a word with a more specific, narrower meaning than demand:

Other hyponyms of demand include claim, take, govern, draw, cost, cry for, cry out for, compel.

demand (noun)	exact (noun)
the act of demanding
required activity
an urgent or peremptory request
the ability and desire to purchase goods and services
a condition requiring relief

demand (adjective)	exact (adjective)
	marked by strict and particular and complete accordance with fact
	(of ideas, images, representations, expressions) characterized by perfect conformity to fact or truth; strictly correct
	lacking compromising or mitigating elements

demand (verb)	exact (verb)
request urgently and forcefully	claim as due or just
claim as due or just	take as an undesirable consequence of some event or state of affairs
summon to court
ask to be informed of
lay legal claim to
require as useful, just, or proper