axehandle
Free Radical
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PH meter
Sorry for spamming, but is EUR60 cheap for a _new_ digital PH-meter?
My PGP key, Fingerprint 5D96 E09E 365D 1867 2DF5 C2FE 4269 9C19 E079 CD35
\"Verbing nouns weirds the language!\"
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Organikum
resurrected
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depends on the electrode(s) you get with the thingie and the amount of calibration liquids.
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axehandle
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Don't know about the electrodes, and 100ml of calibrarion liquid costs almost as much as the meter itself.
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chemoleo
Biochemicus Energeticus
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Homemade Calibration Buffers
Wow, don't even think about buying them!!
You can make your own buffers, with a set pH, if you have the acid/base component of the buffer - i.e. Acetate and acetic acid, H-phosphate or
H2-phosphate etc.
Then you need to know the pK of each, and then u use the Henderson Hasselbach equation to calculate the pH according to
pH = pKa+ log[A-]/[HA].
MUCH EASIER:
check
http://www.bi.umist.ac.uk/users/mjfrbn/buffers/makebuf.asp
There you can choose lots of differnent buffer conditions, and it calculates the required amounts of acid/base - and the pH is SET!!
Hence - don't even think about buying them for 100 euros 
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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axehandle
Free Radical
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Thank you! I never considered making my own buffer solution.
My PGP key, Fingerprint 5D96 E09E 365D 1867 2DF5 C2FE 4269 9C19 E079 CD35
\"Verbing nouns weirds the language!\"
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