[owlpower]

What is the purpose of adding Iodine into a grignard experiment?

I think it has to be either a or b since anhydrous THF is already being used (thus no moisture) and c does not make sense as Mg + THF already gives the grignard reagent.

Looking at a and b, I would think option a makes more sense since creating the grignard reagent already requires Mg and THF - thus Iodine should be used to help the reaction somehow?

[rolnor]

If the correct answer is c, how do you think iodine could activate the magnesium?

[owlpower]

My guess would be either to increase the surface area or react with the surface of Mg which allows the inner part to react in the grignard reaction (Something similar to removing rust on metals)

[rolnor]

Yes, thats right. The magnesium then can start to react with the halide. This is not always nessesary but speeds things up.

[OrganicDan96]

the magnesium oxide layer is pretty impervious