DOC.

33

191

Doc. 33

"SUPPLEMENT"

TO

"A

NEW DETERMINATION OF MOLECULAR

DIMENSIONS"

[Appended

to

the version

of

Document

15

that

was

published

as

an

article in

Annalen

der

Physik

19

(1906):

289-305]

[Annalen

der

Physik

19

(1906):

305-306]

The

new

edition of Landolt

and

Börnstein's

Physical-Chemical

Tables [1]

contains data

that

are

much

more

useful for

calculating

the size

of the

sugar

molecule

and

the

number

N

of

real molecules in

a

gram-molecule.

Thovert

found

(Tables,

p.

372)

that the coefficient

of

diffusion

of [2]

sugar

in

water at

18.5°C

at

a

concentration

of 0.005

mol/liter

has

the value

of 0.33

cm2/day.

Further,

from

a

table

containing

observed values obtained

by

Hosking

(Tables,

p. 81)

we

can

find

by

interpolation

that

in

a

dilute

sugar

[3]

solution

a

1%

increase

in

sugar

content at 18.5°C

corresponds to

a

0.00025

increase in the coefficient of

viscosity.

[4]

Based

on

these data,

one

finds

P

=

0.78*

10"6

mm

and

N

=

4.15*1023.

Bern, January 1906.