Question

The following reaction occurs in aqueous acid solution: NO3– +I– →IO3– +NO2
In the balanced equation, using the smallest whole-number coefficients, what is the coefficient of NO3–?

Answer 1

You need to learn to do these by yourself. Here is a good site that will talk about all of the things you need to know to balance redox equations.
http://www.chemteam.info/Redox/Redox.html

Here is something that will help you get started. N changes from and oxidation state of +5 on the left to +4 on the right; I changes from -1 on the left to +5 on the right.

Answer 2

If you run into trouble I will be glad to help you through. Explain exactly what you don't understand.

Answer 3

So, after I did the half-reactions, I still only got a coefficient for NO_3- to be 1, yet in the answer key provided (this is a practice midterm question), it says the coefficient is 6....I'm confused as to how you are supposed to figure that out.

Answer 4

NO3^- + I^- > IO3^- +NO2
N (on the reactant) oxidation# is 5 (on the product) oxidation# is 4
there will be 1 mole of e- on the oxidation 1/2 reaction
I (on the reactant) oxidation# is 1 (on the product) oxidation#is 5
there will be 6 moles of e- on the reduction 1/2 reaction
In order to balance that given reaction, we have to balance the number of electrons on the redox 1/2 reactions.
6(3H^+ + NO3^- > NO2 + e- + 3H2O)
3H20 + 6e- +I^- > IO3^- 3H^+
________________________________
15H^+ + 6NO3^- I^- > 6NO2 + IO3^- + 15H2O
Now, in the balanced equation, the coefficient of NO3- is 6.