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jumbogala
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Homework Statement
OCl- is reacted with I- in acidic solution to generate I2.
The I2 generated is then titrated using a solution of Na2S2O3.
If you look at the sum of the two reactions above, information about S2O3- can be used to determine the amount of I2 and thus the amount of ClO-.
Give the relevant balanced equations for the titration of OCl- with S2O32-. Including all redox half reactions there are three.
Homework Equations
N/A
The Attempt at a Solution
First I figured out the two equations. I think they are:
OCl- + H2O + 2I- ---> Cl- + 2OH- + I2
I2 + 2S2O32- ---> 2I- + S4062-
Are those correct? Is it different because it's in acidic solution? The OH- make me think I did this in basic solution, but I'm not sure.
Then I added the two equations together to find:
OCl- + H2O + 2S2032- -----> Cl- + 2OH- + S4062-
If the last equation is correct, I don't see how that works. There's no I2 in the equation. The question says I need to go from thiosulfate ion, to I2, then to OCl-... hmm. What am I doing wrong?
Thanks!
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