AquaLab 4TE Series - Page 106

AquaLab 15 APPENDIX A
Table 4: Water Activity of Selected Salt Solutions
Saturated Solution a
w
at 20
◦
C a
w
at 25
◦
C
Lithium Chloride 0.113 ±0.003 0.113 ±0.003
Magnesium Chloride 0.331 ±0.002 0.328 ±0.002
Potassium Carbonate 0.432 ±0.003 0.432 ±0.004
Magnesium Nitrate 0.544 ±0.002 0.529 ±0.002
Sodium Chloride 0.755 ±0.001 0.753 ±0.001
Potassium Chloride 0.851 ±0.003 0.843 ±0.003
Potassium Sulfate 0.976 ±0.005 0.973 ±0.005
Note: Table 4 adapted from Greenspan (1977). Rounded to
nearest thousandth.
4. Saturated salt solutions are very temperature-sensitive and their
values are not as accurate as the verification standards offered
by Decagon.
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