[dagr8est]

I thought that redox reactions only occured when you had an ion and an uncharged substance but I just read that a halogens can act as oxidizing agents to take electrons away from metals such as Mg + Cl₂ -> Mg⁺² + 2Cl^-.

I have a couple questions that say which of the following will undergo a redox reaction:
Br₂ and Pb
Cl₂ and Cu
I₂ and Mg

I have not dealt with this type of problem before and I don't see how to determine whether a reaction will occur or not.  I know that each of those halogens is definately a stronger oxidizing agent than their respective metals.  Does that mean that a reaction will occur for all three of those cases?  Any help will be appreciated.

[syko sykes]

i think they will all react but not really sure on the first one though

on your example, couldn't it also form MgCl₂... i guess this would assume the reactants are ions though. what were you given, elements written with charges (or lack thereof) or elements written out in there full names?

[dagr8est]

I wrote the question exactly as it is written in my textbook.  Also, why unsure about the first one?

[mike]

I believe that you can write the reactions for all of these examples and then using a table of reduction potentials determine which ones and in which direction these redox reactions will be spontaneous.