DOC.
17
JULY
1914 29
17. From Walther Nernst
Berlin,
26a Am
Karlsbad, 2 July 1914
Dear
Colleague,
According
to
ClausiusClapeyron
for the steam
pressure,[1]
lnp
=
+
2.5lnT4 Io^iT
+ C' *
=
W+5/£T
applies.
U
=
energy
content
of
the
rigid body,
C
the
“chemical constant” accord
ing
to
my
heat
principle,
only dependent
on
the
nature of
the
gas, according
to
Sackur[2]
C/2.3026
=
1.45
+
1.5
logM.
We set
according
to
Stern[3] U
=
3R
Bv/Bv/T1;
thus
resulting
in
fr=3ñm(^i)
+
^.
Otherwise,
lnp
=
+
2.5
lnT
+
3
ln
(er

l)

3^
+
C.
or
(T
large!)
lnp
=
iA°+
^^

0.5
ln T
+ 3
ln
ßv
+
C
Stern
commits
the
error
of confusing
C
with
3
ln
ßv
+
C;[4]
his kinetic
result
(following
the
completely
unnatural
model)
is
simply
nonsensical
when
you proceed
from Sackur
or
from
my
theorem.[5]
When in
the
thermodynamic
derivation Stern talks of
“zero point
energy,”
that
is
a
second
very gross blunder;[6]
the above
simple
derivation shows that,
as
is
obvious from
the
outset,
of
course,
such
hypotheses
are
not
used in
thermody
namic
derivations.
“This
was
the
first trick
And
the
second
follows
forthwith.”[7]
Namely,
the
diagram
Best
regards, yours,
W.
Nernst
N.B.
It
is not
worth
considering
further the
confusion, corresponding
to
the
above,
reigning
in Stern’s
L0
and
A0
=
model.[8]