DOC.

10 81

Doc. 10

Review

of

N. N. SCHILLER,

"Some

Concerns

Regarding

the

Theory

of

Entropy

Increase

Due

to

the Diffusion

of Gases

Where

the Initial Pressures

of the

Latter

Are

Equal"

("Einige

Bedenken

betreffend die Theorie der

Entropievermehrung

durch Diffusion der

Gase

bei einander

gleichen

Anfangsspannungen

der

letzteren,"

in

Meyer,

S., ed., Festschrift.

Ludwig

Boltzmann

gewidmet zum

sechzigsten Geburtstage

20.

Februar

1904.

(Leipzig:

J.A. Barth,

1904): 350-366)

[Beiblätter

zu

den

Annalen

der

Physik 29

(1905):

237]

First it is

shown

that

a

homogeneous

gas

can

be

reduced

isothermally

to

an

n-time smaller

volume

without

supply

of

work

and

heat if

one assumes

the

existence of walls that

are

permeable

by a

part of the

mass

of

a

gas

but

not

by

the

rest

of the

mass

of the

gas; according

to

the author, this

assumption

[1]

does not

contain

any

contradiction.

Then

it is demonstrated that the

expression

for the

entropy

of

a system

consisting

of spatially

separated

gases

of

equal temperature

and

pressure

has

the

form

the

entropy

of the

system

after diffusion

can

be represented

by

the

same

formula.

From

this it is concluded that the

entropy

is the

same

before

and

after diffusion.

The

author

arrives

at

the

same

result

by

a

line of

reasoning

[3]

that

cannot be

reproduced

here.

In

this line of

reasoning

one

operates

with

a

surface that

separates

a

chemically

homogeneous

gas

into

two

parts such

that

in

thermal

and

mechanical

equilibrium

the

gas pressure

in the

two

parts

is

different;

it is

(implicitly) assumed

that

during

the

passing

of the

gas

through

this

surface

no

work

is transferred

to

the

gas

by

the latter.

[2]