The Vespiary
The Hive => Chemistry Discourse => Topic started by: hCiLdOdUeDn on December 26, 2002, 07:04:00 AM
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Oxone is a triple salt, 2 KHSO5·KHSO4·K2SO4, with potassium monopersulfate, KHSO5, as its active ingredient.
Most oxy-shock pool chemicals doesnt say 100% Oxone or 85% Oxone on the label but rather something like " Active ingredient: 42.8% Potassium monopersulfate."
People often get confused of oxone percentages. 100% oxone does not mean it is 100% potassium monopersulfate. The molecular weight of the triple salt,oxone, is 614.7g/mol. Potassium monopersulfate(KHSO5) MM=304g/mol. Divide 304 into 614.7 and you get a maximum percentage of 49.4%
So, 100% oxone is 49.4% potassium monopersulfate. So if you want to know the percentage of your "oxone" just multiply your percentage of potassium monopersulfate x 614.7 and divide that number by 304. For example:
.428(42.8% KHSO5) * 614.7= 263.1
263.1 / 304 = .865 * 100 = 86.5% "Oxone"
Now that you know your "oxone percentage" just adjust the ratios in Chromics Oxone writeup and use less buffer!
Sink or SWIM
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The molecular weight of oxone, KHSO5*1/2KHSO4*1/2K2SO4 is 307.4 g/mol. The triple salt, contains two equivilants of potassium monopersulfate, so we're only interested in half of your value of 614g/mol... I believe I did the math correctly here. If I'm in error, please walk through the calculations in detail showing the error.
If you do the math for 100mmol alkene, you use 200mmol potassium monopersulfate. That would lead most people to use 61.5g if you were to follow your own math. However, if you notice in the write-up I recommend using ~72.7g Oxone. This is because even 100% oxone has already started to decompose. According to the literature references I've read, if your oxone is reasonably fresh, it's a good idea to use 10-15% excess above the value that you recommend.
Becareful with the math here, it's super-easy to make a mistake.
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Your right, its always good to use a little more oxone and a little less buffer, IMO.
Sink or SWIM