26 DOC.
5
CONTRIBUTIONS TO
QUANTUM
THEORY
formulation, i.e.,
for
chemically simple, crystallized
substances,
follows.
[p. 828]
However,
when two kinds
of
atoms form
a
mixture,
we
do not leave the
thermodynamic
state of the
system
if
we exchange
two
atoms
of
different kinds. One
then
gets
Z
=
(n1
+
n2)!,
while
for substances
in
a
nonmixed state
Z
= n1! n2!
would be correct. The
equality
of
entropies
at absolute
zero, therefore,
does not hold
in this
case.
Instead,
one gets
for the
difference
in
entropies
between
the substances
in
mixed and
in nonmixed states the
value
R +
n3)!
i\
8
«,!
«s!
'
[21]
which,
of
course,
reduces to
2Rlg2
if
n1 = n2 =
N.