84
REVIEW OF GIAMMARCO
[5] equation
that the
Thomson-Berthelot
rule
must
be
valid
at
low
temperatures,
but that
at higher
temperatures
the
term
-ST lg
T
may
cause
deviations
when
SA
SB.
Doc.
13
Review
of
A.
GIAMMARCO,
"A
Case of
Corresponding
States
in
Thermodynamics"
("Un
caso
di corrispondenza in termodinamica,"
Il
Nuovo
Cimento
5
(5)
(1903): 377-391)
[Beiblätter
zu
den
Annalen
der
Physik
29
(1905):
246]
[1] [2]
If
one
has
a
liquid
(volume
v)
in
a
closed
cylindrical
tube
and above
it its saturated
vapor
(volume
v'),
and
one
plots v/v'
as
a
function of the
absolute
temperature
T
in
orthogonal
coordinates,
one
obtains,
depending
on
the
amount
of the enclosed substance,
a curve
that
has
a
maximum (v/v')max,
or a curve
that is
convex
toward
the
abscissa,
or one
(as
the
limiting case)
that
approaches
the critical
temperature
linearly.
The
author
investigated
ether,
alcohol
and
chloroform in this
way
and
finds that the
above
maxima
(v/v')max
lie
on a
straight line.
According
to
the
law
of
corresponding
states,
two
temperatures
T
and T'
at which
two
different substances
have
the
same
(v/v')max
must
be
corresponding temperatures
(the method
for the
determination
of
corresponding
temperatures), hence
T/Tc
=
T'/T'c.
Using
the
(absolute) critical
temperatures
of ether
(467°),
alcohol
(517°),
chloroform
[3]
(541°) (Bureau
des
Longitudes, 1902),
the
author finds
from
his
observations: