Ferric Chloride is the same thing as Iron Perchloride. You can
search by either name on chemical supplier websites such as
Sigma-Aldrich. There are evidently a lot of synonyms for FeCl3.
Ferric chloride is FeCl2, not FeCl3. One is an iron (II) compound,
and the other is an iron (III) compound with different reactivity. A
search for the “iron perchloride” on sites like the US Sigma-Aldrich
brings up both compounds, most likely because the computer is
returning several close hits for “iron perchloride” which is not in
their catalog.
Ferric chloride is FeCl2, not FeCl3. One is an iron (II) compound,
and the other is an iron (III) compound with different reactivity.
A search for the "iron perchloride" on sites like the US Sigma-
Aldrich brings up both compounds, most likely because the computer
is returning several close hits for "iron perchloride" which is not
in their catalog.
Well this is one of the problems with chemical names, the IUPAC
(International Union of Pure and Applied Chemistry) nomenclature is
iron (II) chloride and iron (III) chloride
All the references I can find in the US list iron (II) chloride as
ferrous chloride and iron (III) chloride as ferric chloride.
In digging I found this definition for the term perchloride “A
chloride having more chlorine than other chlorides of the same
element” So is this a US UK thing or ?
I found a few other synonyms but uniformly ferric chloride is listed
as FeCl3 or iron (III) chloride.
Ferric chloride is FeCl2, not FeCl3. One is an iron (II) compound,
and the other is an iron (III) compound with different reactivity.
This statement is partly correct, partly not.
Yes, the ferric ion is the +3 oxidized state, which means that
ferric chloride is in fact FeCl3, not FeCl2. The latter would be
termed ferrous chloride, in which the iron is in the +2 state. So
that part of the statement is wrong.
The correct part is that iron compounds may contain iron ions in
both +2 and +3 oxidation states. This general usage of the term
“oxidation” here simply means that either 2 or 3 electrons have been
removed from the iron atom. (Chlorine is the oxidizer in the case of
ferric chloride., not oxygen.) Also, metallic iron is what has the
different reactive behavor, not its compounds, as these have already
“reacted.” The first oxidation state is probably going to be +2,
since it is a little more difficult to remove the third electron from
an Fe++ ion.
By the way, iron compounds found in nature may contain iron of either
or both oxidation states. Common rouge and the mineral hematite are
both Fe2O3, in which iron is in the +3 oxidized state. The mineral
magnetite contains both, so it may be thought of as FeO * Fe2O3.
In digging I found this definition for the term perchloride "A
chloride having more chlorine than other chlorides of the same
element" So is this a US UK thing or ? I found a few other
synonyms but uniformly ferric chloride is listed as FeCl3 or iron
(III) chloride."
The prefix and suffixes used are from nomenclature older than IUPAC.
They are often still used, and some are accepted by the IUPAC
nomenclature rules, but not all. IUPAC is almost always more
technically correct, but also more cumbersome.
The older nomenclature is often relative, and a knowledge of the
metal in question is required. For example ferrous refers to iron
(II) and ferric refers to iron (III), however cuprous refers to
copper (I) and cupric to copper (II). The -ous is less oxidized than
-ic, but neither refers to a specific amount. The prefixes like per-
follow suit, where per means more or most. In this case it would
refer to FeCl3 not FeCl2, but would be different for different
metals.
In the US it’s more common to use ferric or ferrous when not using
IUPAC.
Ferric chloride is FeCl2, not FeCl3. One is an iron (II) compound,
and the other is an iron (III) compound with different reactivity.
This statement is partly correct, partly not. Yes, the ferric ion is
the +3 oxidized state, which means that ferric chloride is in fact
FeCl3, not FeCl2. The latter would be termed ferrous chloride, in
which the iron is in the +2 state. So that part of the statement is
wrong."
Quite right, don’t know how I made that mistake. Thanks for catching
it.