* Iodide ion (I-): This is a single atom with a -1 charge. Copper does not exist in a compound with just iodide ions.
* Iodide compound: This could be any compound containing iodine, like copper(I) iodide (CuI) or copper(II) iodide (CuI₂).
Let's analyze the possible scenarios:
1. Copper in a compound with iodide ions (I-)
Copper cannot exist as a simple cation (Cu+) in solution with iodide ions. This is because the iodide ion is a strong reducing agent, and copper(I) is easily oxidized to copper(II) by iodide.
2. Copper in copper(I) iodide (CuI)
* Iodine (I): We know iodine is a halogen and typically has an oxidation number of -1.
* Copper (Cu): Since there's only one copper atom and one iodine atom, the copper must have an oxidation number of +1 to balance out the -1 charge of iodine.
3. Copper in copper(II) iodide (CuI₂)
* Iodine (I): Again, iodine has an oxidation number of -1.
* Copper (Cu): With two iodine atoms (total charge of -2), the copper must have an oxidation number of +2 to balance the charge.
In summary:
* Copper does not exist in a compound with only iodide ions.
* The oxidation number of copper in copper(I) iodide is +1.
* The oxidation number of copper in copper(II) iodide is +2.
