How does the Winkler Titration Method work and what is the chemistry behind it?

[dazza95]

We used the winkler titration method for our dissolved oxygen experiments.
We added magnesium sulphate and sodium iodine.
For all the methods on the internet it says to use manganese sulphate and potassium iodide.
We have to explain how the method works and the chemistry behind it, so does the magnesium sulphate do the same job as the manganese sulphate likewise the sodium iodine does the same job as potassium idodie?

 

[Borek]

We have to explain how the method works and the chemistry behind it

http://lmgtfy.com/?q=winkler+titration

Now, once you will read about the method, at least magnesium/manganese part should be obvious.

I am moving the question to the homework section - as this IS part of your homework.