confidence vs certain

confidence is a noun but certain is not a noun.

Word	Noun	Adjective	Verb	Adverb
confidence	Yes	No	No	No
certain	No	Yes	No	No

confidence (noun)	certain (noun)
freedom from doubt; belief in yourself and your abilities
a secret that is confided or entrusted to another
a feeling of trust (in someone or something)
a state of confident hopefulness that events will be favorable
a trustful relationship

confidence (adjective)	certain (adjective)
	established beyond doubt or question; definitely known
	having or feeling no doubt or uncertainty; confident and assured
	certain to occur; destined or inevitable
	established irrevocably
	exercising or taking care great enough to bring assurance
	definite but not specified or identified
	reliable in operation or effect