Table B–1: Properties of common solvents (continued)
Solvent
Vapor pressure mm Hg
(Torr)
Boiling
point (°C)
Flash
point (°C)
Tetrahydrofuran
142 at 20 °C
66.0
-14
Toluene
28.5 at 20 °C
110.62
4
1,2,4-Trichlorobenzene
1 at 20 °C
213.5
106
Triethylamine
57 at 25 °C
89.5
-9
Trifluoroacetic acid
97.5 at 20 °C
71.8
-3
Water
17.54 at 20 °C
100.0
o-xylene
6 at 20 °C
144.41
17
B.2.1 Solvent miscibility
Before you change solvents, refer to the table below to determine solvent miscibility.
Be aware of these effects:
• Changes involving two miscible solvents can be made directly. Changes involving
two solvents that are not totally miscible (for example, from chloroform to water)
require an intermediate solvent like n-propanol.
• Temperature affects solvent miscibility. If you are running a high-temperature
application, consider the effect of the higher temperature on solvent solubility.
• Buffers dissolved in water can precipitate when mixed with organic solvents.
• When you switch from a strong buffer to an organic solvent, thoroughly flush the
system with distilled water before you add the organic solvent.
Note:
λ cutoff is the wavelength at which the absorbance of the solvent equals 1
AU.
Table B–2: Solvent miscibility
Polarity
index
Solvent
Viscosity
cP, 20 °C
(at 1 atm)
Boiling
point °C
(at 1
atm)
Miscibility
number
(M)
λ
cutoff
(nm)
0.0
N-hexane
0.313
68.7
29
—
1.8
Triethylamine
0.38
89.5
26
—
4.2
Tetrahydrofuran (THF) 0.55
66.0
17
220
4.3
1-propanol
2.30
97.2
15
210
4.3
2-propanol
2.35
117.7
15
—
June 12, 2015, 715004747 Rev. A
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