Thread: What does the II mean exactly in Iron(II)-chloride?

This is a pretty simple question ofcourse, but does the II mean there are 2 Fe's in iron-chloride, or that there are 2 Chlorides? does it refer to the charge of Fe?

Originally Posted by questioner1

does it refer to the charge of Fe?

This is correct. In this case the number of chlorides is also 2 because the charge on chloride is negative 1, and two of these balance out the positive 2 charge on Fe.

thanks!

Strictly speaking, it refers to the oxidation state of the iron ion.

For instance, the dichromate molecule (Cr2 07) has a charge of -2, but the chromium has an oxidation state of +6. If this were to form a compound with potassium, we would call it potassium dichromate (VI).