Chemical Thermodynamics of Tin - Volume 12 - OECD Nuclear ...

364
A Discussion of selected references
These entropy values overlap, but result a) was selected for this review,
because integration of smoothed T, C data yielded also 57.18 J·K −1·mol −1 .
[1978VAS/YAS]
o
p, m
An equation for recalculating thermal effects to zero ionic strength is derived from the
Debye-Hückel relation. Numerical values of the coefficients over a wide range of
temperatures and ionic strengths are given.
The enthalpy of reaction measured at finite ionic strength can be extrapolated
2 ο
to I → 0 by linear regression: Δ H − Δ z Ψ = Δ H + bI .
r
The following table compares the different ionic strength extrapolation
functions used in [1967VAS], [1978VAS/YAS] and [1996PLY/GRE]. The agreement
between [1967VAS] and [1978VAS/YAS] is not as good as expected.
r
Table A-39: Molarity to molality conversion.
I/M
(HClO 4 )
I/mol·kg –1
(HClO 4 )
F(I) M basis/kJ·mol –1
[1967VAS]
F(I) M basis/kJ·mol –1
[1978VAS/YAS]
F(I) m basis/kJ·mol –1
[1996PLY/GRE]
0.1000 0.10077 0.1798 0.2096 0.3203
0.5000 0.51330 0.2588 0.3617 0.5144
1.0000 1.05080 0.2874 0.4353 0.6017
2.0000 2.20380 0.3107 0.5085 0.6853
3.0000 3.47130 0.3218 0.5498 0.7313
4.0000 4.86840 0.3286 0.5779 0.7626
6.0000 8.12820 0.3369 0.6154 0.8048
[1979PAU/STE]
Paukov et al. [1979PAU/STE] measured the heat capacity of SnCl 2 (cr) in the
temperature range of 5 to 304.70 K. The values measured for a sample of high purity
(99.5%) in a rhombic phase (PbCl 2 ) are shown in Table A-40 and Table A-41 . They
estimated the accuracy of the measurements as 0.2% at T > 25 K and about 0.5% at
T < 25 K.
CHEMICAL THERMODYNAMICS OF TIN, ISBN 978-92-64-99206-1, © OECD 2012