L. Zheng et al.
Determination of melting point by freezing point
depression
Acknowledgements The project was supported by the National
Natural Science Foundation of China (21373005, 21673107) and
LNET (LR2015025).
The trace impurities can also make a difference for the
experimental result even the purity of 99 mass% is high. In
that case, IL can be taken as a dilute solution which con-
sists of solvent and impurity. Since the freezing point of
dilute solution is certain to below the melting point of pure
IL, then freezing point depression equation was obtained
according to phase equilibrium principle as follows:
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Ã
Ã
ln x ¼ D H ðT ÀT Þ=RT T
ð10Þ
C
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Ã
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2
] as a suitable solvent for
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de m
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1
1
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2
6
3
6
[
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5 6
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Conclusions
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2
O + [DMIM]DMP system.
de m
90.60 J mol− K−1 and the freezing constant K were also
calculated.
1
=
f
´
1
1
23
Zheng, Ling
