The chemical formula "copper chloride" is not specific enough. Copper can form multiple ions with different charges, leading to different chemical compounds.

Here's why it's problematic:

* Copper(I) chloride: This compound has the formula CuCl and contains copper in a +1 oxidation state.

* Copper(II) chloride: This compound has the formula CuCl₂ and contains copper in a +2 oxidation state.

To be correct, you need to specify the oxidation state of copper.

Therefore, you should use either "copper(I) chloride" or "copper(II) chloride" depending on the specific compound you're referring to.