Hi all list members ; While we are on the subject of pH, can anyone give me a reasonable explanation as to why the pH of pure water is 7.0?? And I don't mean because it is in the middle of the range.
Peter G. Thailand --- bioveging <[EMAIL PROTECTED]> wrote: > And THAT is one of great benefits of this list, the > mountainous > combined experience of it's members ! > Thank you very much for your answer as it helps me a > great deal > knowing that I was not having a "twilight zone" > moment with my PH > meter. Yes, mine does have the little adjustment > knobs and I have > purchased two seperate solutions, one a PH-7 and the > other a PH-10 > and will be doing the calibration today so I can > properly titrate my > WVO for the next batch. > > L. > > --- In biofuel@yahoogroups.com, Guag Meister > <[EMAIL PROTECTED]> > wrote: > > Hi L ; > > > > pH meters go out of calibration VERY easily. The > bulb > > which senses the pH is very delicate. It can be > > easily affected by strong acids or bases, > particularly > > if these solutions are allowed to dry on the bulb. > > > Long periods of exposure to air (in other words, > > drying out) is not a good thing either for the > bulb. > > > > More expensive meters have calibration buttons to > > compensate for this. With these better meters, > you > > buy some calibrated solutions and then regularly > > adjust the meter to read the correct value. > > > > If you are using a cheap meter which does not have > > calibration, here are some tips for longest life > : > > > > 1) These cheap meters are not designed for strong > > acids and bases, so don't use in strong acids or > > bases. > > 2) Rinse the bulb well with neutral water after > every > > reading. > > 3) When not in use, store in a manner such that > the > > bulb is in a pH 7.0 buffer solution. This can be > > readily purchased from a lab supply company, and > not > > expensive. > > 4) Check calibration with pH standard solutions. > If > > your meter is off a little, you can mentally > > compensate, but this is not a true calibration. > To do > > a true calibration you need two points to > establish > > slope and offset. > > > > Hope this helps.. > > > > Peter G. > > Thailand > > > > > > --- bioveging <[EMAIL PROTECTED]> wrote: > > > > > My PH meter seems to be out of whack. Does this > > > happen on any kind > > > of regular basis? > > > The "new" WVO I have is clearly better than the > > > other lot I did and > > > it is titrating even worse than the 10gr/liter > batch > > > and I do not > > > think this is possible so I acquired some PH > > > solution from the > > > aquarium store (one a 7 and another one a 10) > and > > > haven't tested > > > them yet, although I was wondering if anyone > else > > > has had trouble > > > with PH meters going out of sink. > > > I checked two seperate lots of WVO, both better > than > > > the sludge I > > > did my 20 liter with, and they BOTH titrated > higher > > > than 10gr/liter > > > so something is amiss I am sure. > > > I plan on checking my PH meter ASAP and will > post > > > any results, but > > > in the mean time any comments? > > > > > > L. > > > > > > > > > > > > > > > > > > > __________________________________ > > Do you Yahoo!? > > Yahoo! Mail - 50x more storage than other > providers! > > http://promotions.yahoo.com/new_mail > > > __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - Send 10MB messages! http://promotions.yahoo.com/new_mail ------------------------ Yahoo! Groups Sponsor --------------------~--> Make a clean sweep of pop-up ads. Yahoo! Companion Toolbar. Now with Pop-Up Blocker. Get it for free! http://us.click.yahoo.com/L5YrjA/eSIIAA/yQLSAA/FGYolB/TM --------------------------------------------------------------------~-> Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://infoarchive.net/sgroup/biofuel/ Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/biofuel/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
