[Novia]

I did an experiment about synthesis of copper iodide using copper wire, iodine and sodium iodide. The reaction equation provided is 2Cu + I₂ 2CuI . I have some questions about this.
1. Teacher said sodium iodide has 2 roles in this experiment, I know that one role is to dissolve iodine, what is the other role of it?
2. Why I₂ can react with copper to form CuI, but I^- from NaI will not react with copper?

Thank you.


Mod edit: fixed right arrow typo

[Borek]

What were your observations? What happened during the experiment? What form is the CuI?

Do you know what a redox process is?

[Novia]

What were your observations? What happened during the experiment? What form is the CuI?

Do you know what a redox process is?

the solution containing iodine and sodium iodide changed colour from brown to colorless after heating with copper wire,meaning all I₂ have been reacted with copper to form CuI.
the CuI obtained was in aq form and precipitate out after cooling in cold water.
Now I understand why NaI will not react with Cu, because this is a redox reaction, Cu is being oxidized, meaning I need to be reduced, but I in NaI cannot be reduced.

But I still cannot find out the second role of NaI other than helping to dissolve I₂