A system of physical chemistry - Index of

booksnow2.scholarsportal.info

A system of physical chemistry - Index of

ii8 A SYSTEM OF PHYSICAL CHEMISTRY

nucleus and kept in equilibrium by two rings of greater radius than the

one just mentioned, each of these two rings containing 3 electrons ; the

latter rotate in parallel planes round the axis of the system and are

situated relatively to each other in such a way that the electrons in the

one ring are opposite the intervals between the electrons in the other.

If we imagine such a system broken up by slowly removing the hydrogen

nuclei we should obtain two positively charged hydrogen atoms

and an oxygen atom with a double negative charge in which the outermost

electrons will be arranged in two rings of three electrons each, the

two rings being parallel to one another.

Parson's Magneton and the Structure of the Atom.

Hitherto, in dealing with the problem of atomic structure, we have

regarded the electron as a minute discrete particle of electricity or

matter, assumed to be spherical, and capable of movement " inside "

the atom in certain orbits, the velocity of movement being relatively

small compared with the velocity of light. A new concept has been

introduced, however, in connection with the electron which must be

very briefly discussed. According to this view the electron itself is a

tiny ring or annulus carrying a negative charge. The ring is regarded

as rotating continuously with a peripheral velocity which is of the same

order as that of light. This is equivalent to a circuit current, analogous

to the Ampere currents assumed to account for magnetism, and consequently

such a structure possesses magnetic properties. For this reason,

A. L. Parson, to whom this concept of the electron is due {Smithsonian

Inst. Ptib., 65, No. II, 191 5), substitutes the word mag?teton in place of

electron.

The term magneton was first introduced by Weiss in 191 1 {cf. N.

Campbell's Modern Electrical Theory). On the

theory

basis of the electron

of paramagnetism an expression has been deduced for the susceptibility

according to which this quantity should be proportional to

M-'/T, where M is the magnetic moment of a molecule and T is the

absolute temperature. Weiss observed that in the case of magnetite

over a certain temperature range the curve connecting the susceptibility

with the reciprocal of the temperature was not a straight line through

the origin, as it should have been, but consisted of a series of lines

separated by definite differences in the value of the susceptibility.

This was ascribed by Weiss to abrupt, discontinuous variations in the

value of the molecular magnetic moment M, and Weiss further showed

that the various observed values were all even multiples of a certain

quantity to which he gave the name the magneton. The magnitude

[i.e. the moment) of the magneton is the same as that which would be

produced by a rotating electron revolving in an orbit of radius 10"^ cm.

with a frequency of 10^* per second approximately. Weiss of course

kept to the classical concept of the electron.

In the case of Parson's ring electron or circuit current the radius of

the ring is estimated to be about 1-5 x 10"^ cm., that is a quantity

More magazines by this user
Similar magazines