Hello Neville,
Distilled water has a specific gravity of 1.0. So, if you could measure a specific amount, EIS should have a higher specific gravity. I would have to think about translating between specific gravity and PPM, but there may be something there. Tom From: Neville Munn [mailto:one.red...@hotmail.com] Sent: Sunday, February 20, 2011 2:18 PM To: silver-list@eskimo.com Subject: RE: CS>pH calibration fluid? Thanks Tom/Frank. I eventually found some information that explained it a little more, that's when I had the 'light bulb moment' and understood that a buffer of 7.01 referred to the testing of a known or preferred pH level one may be aiming for. Until I found that I thought it would be alright to use when the readings never go under 7.0. I only need to range from 7.0 up to 10.0, or praps higher. I had a sample tested shortly after production a while ago and it went >9.0, so I guess their equipment was calibrated to only go up to 9.0. I'm curious to find out how high that pH level would be *immediately* after production...that's why I was looking into getting some sort of metering device. I don't really want to use those litmus strip thingo's, they'd be a tad too 'iffy' for my liking. Pity a refractometer wouldn't work, but it appears they only read glycol and Specific Gravity. Pity a simple hydrometer couldn't be invented for this stuff too, measuring the weight or Specific Gravity of silver in water, now *there's* something that would be very handy, between a TDS/PWT or EC/TEMP meter and a hydrometer one would pretty much have the best of everything. P.S. I just had a quick google and it appears hydrometers are used to measure silver in photography solutions...will go and look a little closer into that. N. _____ From: po...@prodigy.net To: silver-list@eskimo.com Subject: RE: CS>pH calibration fluid? Date: Sun, 20 Feb 2011 09:30:01 -0800 Hello Neville, When using single point calibration you generally use a calibration solution that is close to what you are trying to measure. If your solutions are close to a PH of 7, the 7.01 calibration solution will work well. If you are measuring over a wide range of PH, you would typically do a triple point calibration using calibration solutions of PH 4, PH 7 and PH 10. One nice thing about the triple point calibration is that it alerts you when your PH probe is wearing out. Tom From: Neville Munn [mailto:one.red...@hotmail.com] Sent: Saturday, February 19, 2011 4:57 PM To: silver-list@eskimo.com Subject: CS>pH calibration fluid? Can someone help me out here re: specifically a *single point* calibration? If one does not need to calibrate below base 7 or below in the acidic range, is a buffer solution of 7.01 adequate? I know one can calibrate to determine ranges between two desired figures, but using two buffer solutions would only be required if measuring both adicity *and* alkalinity would it not? If measuring *above* 7.0 only, or in the alkaline range, I would assume two calibration points would not be necessary as the reading would/should never go below 7 in this instance...Yes/No? Thanks N.
