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

130
VII Tin oxygen and hydrogen compounds and complexes
and
T
ο ο ο
m
−
m ∫ p,m
0K
H ( T) H (0K)= C dT
have been calculated using Eq. (VII.25). In order to obtain consistent uncertainties two
ο
T, C data sets were prepared by adding and subtracting the expression
p,m
{ C (obsd) − C (calc)}
ο ο 2
p,m p,m
ο
ο
from individual C p,m
values. These sets of C p,m
values were approximated by
ο
Eq. (VII.25) again. Integrating of thus modified C p,m
functions resulted in lower and
upper S ο
( T)
ο ο
m
and Hm( T) − Hm(0K)
values, respectively. The uncertainties of
ο
ο
ο
S m
(298.15 K) and Hm(298.15K) − H m
(0K)
were estimated by dividing the difference
of the lower and upper values by two.
ο
Figure VII-11: C p,m
(SnO 2 , cass), extrapolation to T → 0.
/ J·K–1·mol
–1
10·C o p, m
16
14
12
10
8
6
4
first 17 data pairs, both refs.
[2004GUR/GAV2] model
[1980ZHO/KOS] extrap.
[1981BAC/HSU] C° V
, Θ D
= 500 K exp. data
[2004GUR/GAV2]
[1980ZHO/KOS]
T = 16 K
2
C° p, m
= 4.11 × 10 -5·T 3
C° p, m
= 2.51 × 10 -5·T 3
0
0 5 10 15 20 25 30
10 –3 (T / K) 3
ο
Table VII-5 shows that conventionally obtained values of C p,m
(298.15 K),
ο
ο
ο
S m
(298.15 K) and Hm(298.15K)
− Hm(0K)
agree with those obtained by Gurevich et
al.’s model within the range of uncertainties given by [2004GUR/GAV2] and
[2004GUR/GAV3]. The uncertainties estimated by the method outlined above are
somewhat more pessimistic than those of Gurevich et al.
CHEMICAL THERMODYNAMICS OF TIN, ISBN 978-92-64-99206-1, © OECD 2012