take a chance vs risk

take a chance is not a noun while risk is a noun.

Word	Noun	Adjective	Verb	Adverb
take a chance	No	No	Yes	No
risk	Yes	No	Yes	No

As verbs, take a chance and risk are synonyms defined as:

Other synonyms of take a chance include adventure, chance, gamble, hazard, run a risk, take chances.

take a chance (noun)	risk (noun)
	a venture undertaken without regard to possible loss or injury
	the probability of being exposed to an infectious agent
	the probability of becoming infected given that exposure to an infectious agent has occurred
	a source of danger; a possibility of incurring loss or misfortune

take a chance (verb)	risk (verb)
take a risk in the hope of a favorable outcome	expose to a chance of loss or damage
	take a risk in the hope of a favorable outcome