9.1 Winkler Experiment for Dissolved Oxygen (Chemical equations too) [SL IB Chemistry]

Cartoon, actual experiment then chemical calculation and explanation

[declan.fleming]

this video saved my neck .. I wasted hours playing around with various recipes out there but in the end the bucket chemistry approach to the initial steps worked best for me too :)

[plasticyarn]

The intro was cool. Thank you for making this video.

[Rrrrriley]

This was so incredibly helpful. Thank you!!

[ImRunToFilm]

You explained it the best out of everyone

[olorunfemiadeboye]

Simply a good choice from you man...you've really ease my burden sir

[sebnemfener]

I have a question, what would happen if the sample solution was not saturated with oxygen? I thought measuring the oxygen already present and then waiting 5 days to measure it again would be suffiecient to see the BOD.

[moguersa]

Hi Mr Thornley, thanks for share your knowledge with us. I would like to know what is the concentration of the titrant solution.

[ibnadam]

extremely helpful, you didn't wear any protective gloves which is hazardous especially working with sulphuric acid. However great video.

[wall.eandhuss]

Awesome video!! Very entertaining as well!

[sungod]

Hi Mr. Thornley. May I ask why we have to increase the pH of the solution before we start adding the sodium thiosulfate? Also why specifically allow the floc to settle to the halfway point of the flask and not all the way?

[amritkaurbal]

i just have two question
1) why dont we double the moles from MnO2 (middle eqaution) : 2MnO2(Top Equation) even though that is the relation observed by the mole ratio
2) why is oxygen concentration to 2 sigfigs when we used 3 sigfigs for others

[jaybagoandas]

Dear Mr Thornely, thank you very much for giving us knowledge about quantifying the Dissolved Oxygen in water through Winkler method.
However, I wanted to ask if pH affect the concentration of DO?

[jlchan]

Thank youuu your calculation did help a lot!

[litaz]

5:53 is sodium thiosulfate inside of the burette?

[DeDe-yy]

I do the method but the solustion is pink do you know What's the problem ❤

[SaloniMore]

If Winkler titrations do come up on the exam, will we be given these equations as part of the question?

[claireoverholt]

is it not necessary to let the sample sit for 5 days after reagents added but before titration? I thought that was how you calculated BOD. please help!!!

[leenasever]

Hi Mr. Thornley. I was trying to do this experiment with all the same chemicals except for the iodide source, where I had access to potassium iodide instead. But when I added both the manganous sulfate and the potassium iodide, they both simply dissolve and do not result in any formation of floc. I am also using pond water. Do you know why this is happening and if there’s any solution for it?

[hadilankous]

I have a question sir usually in Winkler methods we use Mncl2 why this time we used Mnso4?

[Matthewsss]

Could I ask how much manganese sulfate powder has to be added in terms of weight? Because it wasnt stated