What are the other components of the reaction mixture from Part A that reacts with NaOH before the copper ion? I added sodium hydroxide to...

Cu(NO3)2 is aqueous and exists as Cu(2+) ions and NO3(-)
ions. NaOH is also aqueous and exists as Na+ and (OH)- ions. When the two are mixed
together, the Na+ ions combine with the NO3- ions to form NaNO3 which is aqueous and the
Cu(2+) ions combine with the (OH)- ions to form Cu(OH)2 which is not aqueous and forms a
light blue precipitate. This is an example of a double exchange
reaction.

You say that the reaction takes some time before
you can see the precipitate. But there is no other intermediate compound being formed as
part of the reaction between Cu(NO3)2 and NaOH. All reactions take some time before the
end product is formed after the mixing of the initial compounds. In some, this duration
is very short and they seem instantaneous; in others the result may take longer to show
up.