[illio]

Hey everyone,

I'm doing a Winkler titration with the salt concentration of my water samples as the independent variable.
However, I have a small question about preparing my samples. I don't exactly when how I should add the salt into the water. My procedure is pretty standard - add the water to a bottle followed immediately by the manganese (II) sulfate and alkaline iodide. Stopper and mix, then add sulfuric acid.

So my question is would it be better for me to add the salt to the water before I even add it to the bottle or would it be better for me to add it after I put it in the bottle and before I add the manganese (II) sulfate?

Sorry if this seems insignificant but I'm just worried that adding the salt at the wrong time would have negative effects on my results.

Thanks!

[Borek]

You should keep the solution isolated from the atmospheric oxygen, so putting it into bottle as fast as possible seems to be the best course of action.