[fobbz]

I am a bit confused as to how to find the analyte concentration, let's say Vitamin C in a reaction performed using Iodometric titration. For starters, say I titrate  with 33.45mL KIO3 at a [] of 2.030x10^-3 M.
I have 25.00mL in my erlenmeyer of say Orange Juice. I calculated through stoichiometry of the reaction that I would end up with 2.0371x10^-4 mol of Vitamin C.

Now is where I am not 100% of the [] of the Vit C. I think that the [] will be the the mols Vit C / 25.00mL , the original volume of substance containing the Vit C. But for some reason the fact that adding the two substances makes me want to believe the final vol is 58.45mL.

However thinking about this I am starting to realize it is probably 25.00mL as that was the original sample volume.

Am I correct in this thinking process?

[Borek]

You are confusing initial concentration (which you want to find) with the final concentration of the titration product. Final volume is 58.45 mL, but you are looking either for the initial concentration or for the number of moles in the initial sample - so it is 2.0371×10^-4/0.025 M (assuming you calculated number of moles correctly).

[fobbz]

Awesome thank you!