Copper additions to wine
Copper is added to wine in the form of Copper Sulfate pentahydrate (CuSO4 • 5H2O), a blue crystalline powder. The active ingredient in Copper Sulfate is the copper ion.
The addition calculations on this site all assume you're using Copper Sulfate pentahydrate, as opposed to metallic copper or straight Copper Sulfate (the green stuff).
So when people talk about a copper addition rate or copper solution they are talking about the rate of the copper ion (Cu+2), not the entire CuSO4 molecule. CuSO4 is about 25% copper by weight, which is why you have to add about 0.4 ppm of CuSO4 to get 0.1 ppm of Cu+2.