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

392
A Discussion of selected references
[1986BAN]
Although the equilibrium:
Sn(l) + O 2 (g) SnO 2 (s)
(A.78)
was studied many times using various techniques (see Table A-58), Bannister
[1986BAN] used a novel reference electrode and studied Reaction (A.78) using
potential measurements on the solid-electrolyte oxygen-concentration cell:
Sn(l) SnO 2 (s) | ZrO 2 + Y 2 O 3 | (0.001O 2 + 0.999N 2 )
with a reference electrode of {Pt + (U 0.38 Sc 0.62 )O 2 ± x } powder and, separately, a
ο
conventional porous Pt reference electrode. Between 673 and 1167 K, Δ rGm
((A.78),
T ) = − (571.4 + 0.2030 T ) ± 0.6 kJ·mol –1 . Third-law analysis of the results gives
ο
Δ rHm(A.78) = − (578.0 ± 1.4) kJ·mol –1 , in good agreement with the most recent
calorimetric determination.
Table A-58: Values of the standard molar Gibbs energy change Δ rGm
((A.78),
T )/kJ·mol –1 = A + B (T/K) obtained from the literature. The information in brackets
indicates the reactive gas mixture or reference electrode used. Table modified from
[1986BAN] with several additions.
ο
Reference T/K Technique A/ B/
kJ·mol –1 –1
kJ·K
–1·mol
r
ο
Δ G (1000 K)/
m
kJ·mol –1
[1956PLA/MEY] 806 − 1107 Gas equilibrium (CO + CO 2 ) − 581.0 0.2112 − 369.8
[1960ATA/UTA] 973 − 1148 Gas equilibrium (H 2 + H 2 O) − 572.6 0.2032 − 369.4
[1965BEL/ALC] 773 − 983 Solid-electrolyte (Ni + NiO) − 585.6 0.2132 − 372.4
[1972OIS/HIR] 1173 − 1373 Solid-electrolyte (Ni + NiO) − 562.6 0.1953 − 367.3
[1975PET/FAR] 773 − 1380 Solid-electrolyte (Ni + NiO) − 578.6 0.2085 − 370.1
[1977SEE/STA] 990 − 1373 Solid-electrolyte (Ni + NiO) − 577.4 0.2088 − 368.6
[1978RAM/BAR] 773 − 1173 Solid-electrolyte
(Cu + Cu 2 O)
− 573.8 0.2035 − 370.3
[1978IWA/YAS] 1023 − 1273 Solid-electrolyte (Ni + NiO) − 586.7 0.2144 − 372.3
[1982SUG/KUW] 773 − 1165 Solid-electrolyte (Pb + PbO) − 574.2 0.2049 − 369.3
[1983KAR/THO] 1041 − 1351 Solid-electrolyte (Pt/O 2 ) − 579.7 0.210 − 369.7
[1983KAM/OST] 1073 − 1273 Solid-electrolyte (Pt/air) − 576.6 0.2087 − 367.9
[1986BAN] 673 − 1167
(useful range)
Solid-electrolyte − 571.4 0.2030 − 368.4
[1994YAN/SUI] 720 − 990 − 574.33 0.202 − 372.33
[2001MAL/EDW] 772 − 1206 − 568.9 0.200 − 368.9
The published gas compositions or cell potentials in Table A-58 have been
ο
converted to values of Δ G using JANAF values for CO(g), CO 2 (g), H 2 O(g), Cu 2 O(s),
r
m
CHEMICAL THERMODYNAMICS OF TIN, ISBN 978-92-64-99206-1, © OECD 2012