[chanelo]

"The quantity of antimony in an ore can be determined by an oxidation-reduction titration with an oxidizing agent. The ore is dissolved in hot, concentrated acid and passed over a reducing agent so that all the antimony is in the form of Sb³⁺_(aq). The Sb³⁺_(aq) is completely oxidized by an aqueous solution of BrO₃^-_(aq). Complete and balance the equation for this reaction in acidic solution."

My answer was
 BrO₃^-_(aq) + 3Sb³⁺_(aq) + 6H⁺_(aq)  Br^-_(aq) + 3Sb⁵⁺_(aq) + 3H₂O_(l)

I've tried going through it over and over and keep getting this same answer, which is wrong. Can someone please tell me what's wrong with this equation?

[Borek]

Show how you are balancing.

[AWK]

The balancing is correct
check in
http://www.webqc.org/balance.php
and compare with
http://www.chemteam.info/Redox/WS-redox-titration-problems.html

[chanelo]

Sure, this is my work:

BrO₃^-  Br^-
BrO₃^-  + 6H⁺ + 6e^- Br^- + 3H₂O

Sb³⁺  Sb⁵⁺ + 2e^-
3Sb³⁺  3Sb⁵⁺ + 6e^-

Combined, e^- cancel out:
3Sb³⁺ + BrO₃^-  + 6H⁺ 3Sb⁵⁺ + Br^- + 3H₂O

[Borek]

Very good. And why do you think it is wrong?

Are atoms balanced?

Are charges balanced?

If they are, the equation is balanced, period.

[chanelo]

Everything looks balanced to me but Sapling keeps saying it's wrong.

[Borek]

Hard to say. Can be some bug. People often complain about the way answers have to be entered into these automatic systems.

What I don't like about the equation is that there is no such thing as Sb⁵⁺. Sb is oxidized to Sb(V), but it is not present as the naked +5 cation.

[chanelo]

Yup, you're right, it was just a bug. The answer was right, not sure why it wasn't accepting it. Thanks!