Phosphorus Acid

[Shane_Warne]

I guess your table nees to specifiy the purity of Phosphorus acid used and also the time and temp relationship to the differnt purity's

OK, well I'm trying to work out reasonable assessment of purity following preparation, so that the other reagents are easier to calculate.

Since the reaction rate halves every 10C decrease. (Or is that only for reactions under inert gas?)

Let's say a quantity takes 5mins this time, to completly
oxidize at 180C:

5min @180C
10min @170C
20min @160C
40min @150C
80min @140C
160min @130C
320min @120C
640min  @110C
1280min @100C
2560min @90C
5120min @80C
10240min @70C
20480min @60C
40960min @50C
81920min @40C
163840min @30C
245760min @25C
327680min @20C

There's also the evaporative cooling on the surface.

It's heated in industry to 70C under vacuum for 99% purity H3PO3. They do this because they have researched and vigorously tested information that Jack-all oxidation occurs in solution.

[hypo]

> Since the reaction rate halves every 10C decrease.

that's only a rule of thumb of course! don't expect better than the order of magnitude out of this.
google for "arrhenius" for a better, but still, approximation.

[Shane_Warne]

that's only a rule of thumb of course! don't expect better than the order of magnitude out of this.
google for "arrhenius" for a better, but still, approximation.

Thanks hypo! Ill look at it more closely later (it's a bit more complicated) to see if I can get the correct values for the equation.