oxidation #'s in [Re2Cl9]2-

[kankerfist]

Sorry about no latex, when I try using latex my formulas just wind up as a link
that says "LaTeX graphic is being generated. Reload this page in a moment."


Anyway, I was trying to balance a redox equation and I am completely stumped
as to how:

[Re2Cl9]^2-

can be possible. I'm aware that some arrangements can cause the same atoms
in an ion to have different oxidation numbers, but I can't seem to figure out how
that molecule can exist under any arrangement. Any hints would be appreciated

[ssb]

Sorry about no latex, when I try using latex my formulas just wind up as a link
that says "LaTeX graphic is being generated. Reload this page in a moment."


Anyway, I was trying to balance a redox equation and I am completely stumped
as to how:

[Re2Cl9]^2-

can be possible. I'm aware that some arrangements can cause the same atoms
in an ion to have different oxidation numbers, but I can't seem to figure out how
that molecule can exist under any arrangement. Any hints would be appreciated

To help with latex, ive seen that message when i try to preview a post but if i actually make a post then it will show up. Sometimes I make an error in my latex and i can just edit it real fast. Just try to post some latex and not preview see if that works.

[ssb]

unless you get this error then you really did something wrong
\LATEX

[kankerfist]

Ok, I'll test it by quoting someone that used it sucessfully.

^{33}_{17}Cl^{16}\xrightarrow{n,n}~^{31}_{15}P^{16 }+~^4_2He^2

[ssb]

There You Go. Now see if you can edit your first post with some good code!
Im looking forward to your work!

Edit: You the man

[kankerfist]

{ReCl}_5} + {{H_2}O}
-->
{Re_2}{Cl_9}^{2-} + {ReO_4^-} + {Cl^-} + {H^+}

[ShawnD]

Anyway, I was trying to balance a redox equation and I am completely stumped
as to how:

[Re2Cl9]^2-

can be possible. I'm aware that some arrangements can cause the same atoms
in an ion to have different oxidation numbers, but I can't seem to figure out how
that molecule can exist under any arrangement. Any hints would be appreciated

It's possible for atoms to have a charge that isn't a whole number, or the number can be very different from what is expected. For example, what is carbon monoxide, CO? Does the oxygen have 4 bonds? Does the carbon have 2 bonds? Do they compromise to make 3 bonds each? (edit: I looked it up and yes they make 3 bonds each).
The number of bonds between atoms or groups of atoms is called the Bond Order (http://en.wikipedia.org/wiki/Bond_order).
From that link "A good example of this is bonds between carbon in the molecule benzene where the delocalized molecular orbitals contain 6 pi electrons over six carbons essentially yielding half a pi bond. Together with the sigma bond the bond order is 1.5"

Is it possible that Re has a bond order of 3.5? Sure, why not? :smile:

[kankerfist]

{ReCl}_5} + {{H_2}O}
-->
{Re_2}{Cl_9}^{2-} + {ReO_4^-} + {Cl^-} + {H^+}

Ok, finally figured it out above. I am trying to balance this equation, and in order to break it into half reactions, I need to know the ox #'s of each atom to see which is the reduction half and which is the ox half. If the Re is 3.5 like you say, then am I on the right track that the oxidation half reaction is:
2 ReCl5 + 3e- --> {Re_2}{Cl_9}^{2-}

edit: sorry, I mean reduction half

[Borek]

The best approach is to assume that oxidation numbers (http://www.chembuddy.com/?left=balancing-stoichiometry&right=oxidation-numbers-method) are just an accounting device and they don't refer to any real chemical property.

Borek
--
Stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)
www.pH-meter.info/pH-electrode (http://www.ph-meter.info/pH-electrode)