How many atoms of cupper nitrate?

Answer 1

I am assuming you're asking how many atoms are in copper nitrate.

There are two compounds that could be called copper nitrate copper(I) nitrate, CuNO3 and copper(II) nitrate Cu(NO3)2

The working for Cu(NO3)2 is as follows:

Cu tells you that there is one copper atom N tells you that there is one nitrogen atom, and O3 tells you that there are three oxygen atoms. That would make five atoms, but the NO3 is in parenthesis with a two after it. That means the NO3 occurs twice. This gives you a total of 9 atoms. Was that the question? This compound also breaks down into ions it gives a total of three ions one copper ion and two NO3 otherwise known as nitrate ions.

The same working applied to CuNO3 would give you 5 atoms

I have not seen this question phrased in this manner. Often you will be given a mass and asked how much of this compound is in this mass of the substances.