682
DOC.
639
OCTOBER
1918
I
had
chosen
copper
chloride
not
only
because it
occurs
both with
and
without
crystallization
water
but, above
all,
because
both
types are,
at
the
same
time,
soluble in alcohol.
The
99.8%
alcohol used for
the
solution
had
n
=
75.5
s.
The mol.
vol.
would
thus,
according
to
the
increase in
vol-
ume,
be
ca.
0.3-0.35
but
according
to
the
friction
(K
=
5)
ca.
0.96.
Unfortunately,
I
do not have
the table
for
the
alcoholic solutions of
anhydr.
CuCl2.-
The
molecular volume results
consequently
are
From
Vol.
Increase Friction
Spec.
Vol. Friction For
Spec.
Hydrous
(Hydrous)
Wt.
of Increase Alcohol
CuCl2+
Wt.
Hydr.
Alcoh.
2H2O
Dry
Solutions
0.41
0.40
0.36 0.125 0.32
0.96
CuC12
0.33 0.17 mean
0.41
mean
anhydr.
(0.36 CuCl2
+
2
H2O)
Although
the
differences
existing
in these
figures
are
not substantial, consider-
ing
the
wide
margins
of
error,
one can
nevertheless
certainly
conclude from
them
that
CuCl2
+
2 H2O
does
not
release all
of
its
water, at least, to
the
aqueous
solution and
that
water
is
added
to
the
anhydr.
CuCl2
compound.
g
CuCl2
+
2
H2O cc
Alcohol
ccm
Solution
n'
2
98 98 80
s
4 96
almost
97
88
6
94
”
96 97.5
10
90 93.5 112
14 86 90.5 129
.
-o-
The
important questions
to ask in advance of all such
experiments
and
con-
clusions would
be,
of
course,
whether
the
assumptions
on
which
you, Professor,
based
your
friction formula also
apply
to real
solutions,
furthermore,
whether
it
is
admissible to set
K
=
5
in this formula.
The
questions regarding
all these solutions
interest
me so
particularly
because
I
always
think that
only
after
a complete
clarification
of all
aspects
of the
problems
regarding
inorganic
solvents
can
there be
some prospect
of
success
in
attempting
the
study
of
complicated organic
liquids
and because
surely
at least
part
of
the
immunity puzzle
is
of
a
physical
nature.
That
is
why
I
also
beg you
not
to
take
offense,
if I turn to
you
with
a
request
for
your
advice and
support.-