mix vs mix in

mix is a noun but mix in is not a noun.

Word	Noun	Adjective	Verb	Adverb
mix	Yes	No	Yes	No
mix in	No	No	Yes	No

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

As verbs, mix and mix in are synonyms defined as:

mix (noun)	mix in (noun)
the act of mixing together
an event that combines things in a mixture
a commercially prepared mixture of dry ingredients

mix (verb)	mix in (verb)
mix together different elements	cause (something) to be mixed with (something else)
add as an additional element or part	add as an additional element or part
combine (electronic signals)
to bring or combine together or with something else
mix so as to make a random order or arrangement
open (a place) to members of all races and ethnic groups