The equation, Indicate whick element is oxidized, which is reduced and which is unchanged.?

Question

CrCl3+3FeCl2=CrCl6+3FeCl3

Oxidized________________

Reduced________________

Unchanged__________________

Answer 1

It may be easier to see if you break it down into two half-reactions.

Cl is a spectator ion.  For now, let's "ignore" it.

We see that we have CrCl3 on the left side. Since each Cl-has one negative charge, and we only have one Cr to balance charge, the charge on Cr must be +3

On the right side of the equation we have 6 Cl, each at -1 charge. This means Cr is in a +6 oxidiation state.

Cr+3--> Cr+6 + 3e-

Recall LEO-GER

Lose electrons--oxidation

Gain electrons--reduction

We lose electrons, so this is an oxidation.

--

Now, Fe+2 + e- --> Fe+3   ==> Looking only at charge balance.

We see that electrons are gained; thus, this is a reduction.

Cr is oxidized; Fe is reduced; Cl is unchanged.

I hope that helps.