I know, replying to my own post. No class at all :) > In order to get good oxygen data, you'll need to (1) get the reaction > temperature controlled. [The AP system has a very nice hot block which can > take 120+ tubes at 70 degrees and automatically overflush with helium AND > dump in the acid] (2) Make your phosphoric acid up to an SG of about 1.93 > by adding P2O5 on a hot plate. This is tricky, and pretty dangerous, so if > you want a technique for it, I can email it to you. Just ask nicely, 'cause > I've got to type it from paper copy :-) After getting inundated with request (sic), I typed up the technique we use for >1.92 SG H3PO4. I've dumped it onto a web server for anyone who wants it: http://pc-23.surrc.gla.ac.uk/Phosph.rtf I've used good ol' RTF, 'cause (a) it can't contain viruses, and (b) you can use it on any WP without arguing over file formats. I hope this is of some use to you all, Any questions, just ask :-) Andrew