6L.9

[Sid Panda 3A]

(a) Write balanced half-reactions for the redox reaction of an acidified solution of potassium permanganate and iron(II) chloride. (b) Write the balanced equation for the cell reaction and devise a galvanic cell to study the reaction (write its cell diagram).

How do we know that the chlorine in iron(II) chloride will not be a part of the redox rxn? The solution does not have it in the oxidation rxn ?

[Yasmina Zaarour 1G]

Most compounds with chlorine in them are soluble in aqueous solutions, so the iron (III) chloride will be dissociated into Fe3+ and 3Cl-. The same applies for the potassium permanganate; it will dissociated into K+ and MnO4-. When the iron chloride and potassium permanganate are oxidized/reduced, the oxidation states of Cl- and K+ remain the same because that is their most stable state.

[Rohit Srinivas 2D]

Oxidation number rules can help with this. You know that halogens will be -1, and that alkali will be +1. This means those substances are highly unlikely to change.

[edward_brodell_2I]

Because it is ionic and we need the Fe to take its lower energy state and Cl is a salt bridge ion it wont partake in the reaction.