Very nice - one criticism - when doing the serial dilution you really shouldn't use the same dropper repeatedly because a tiny amount of the original high concentration solution will remain on the dropper and increase the concentration of the last couple of dilutions.

Wow! Thank you for this video! I water batteries for a lot of off-grid solar powered homes and was wondering how to test for lead in the boxes where the batteries go. The boxes are usually lined with EPDM rubber to contain any acid that may spill from them but I always wonder if I am exposing myself to lead when I am watering and replacing them..

What was the point of the Acetic Acid solution?

Sweet. Thanks!

What kind of extraction reagent did you use?

Is there a way to convert Na2SO4 to Na2S? Reductor of some kind?

nice video

they always round it up, but for analytical purposes like GC, HPLC and the like you can also test in FID that no chemical is pure and even the super pure ones on say, Sigma Aldrich are never 100% pure

love the video, but you cant get 100% of any chemical. there is always something to contaminate it so its never completely pure. other than that, great video

part per million

But you're saying that 99.77%=100%, which isn't true.