detitta at hwi.buffalo.edu
Thu Sep 14 12:07:43 EST 1995
PEG concentrations can bemeasured quite accurately by refractometry
(you remember the good old refractometer from p chem days, don't you?).
The refractive index of PEG 8000 is related to the concentration
measured in %(w/v) by
[PEG8000] = (N - b) / a where N is the refractive index and
a= 0.0013889, b= 1.3325
these values are for 24C - there is a small temperature correction
for other temperatures. The relation holds for [PEG] in the range of
1%(w/v) to 50%(w/v).
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