Iron is the most paramagnetic of all substances. Other paramagnetic
metals are: Nickel, cobalt, manganese, platinum, cerium, osmium,
palladium. Diamagnetic metals are bismuth, antimony, zinc, tin, mercury,
lead, silver, copper, gold, arsenic. Bismuth is the most diamagnetic of
all metals.
Of gases oxygen is most paramagnetic. Becquerel calculated that a cubic
yard of oxygen condensed would act on a magnetic needle as powerfully as
5.5 grains of metallic iron. Liquefied oxygen will adhere to the poles
of a magnet.
Changes of temperature and of other conditions may affect a body's
magnetism. Thus hot oxygen is diamagnetic, and a substance paramagnetic
in a vacuum may be diamagnetic in air.
Of liquids, solutions of iron or cobalt are paramagnetic; water, blood,
milk, alcohol, ether, oil of turpentine and most saline solutions are
diamagnetic.
Paramagnetism.
(a) The science or study of paramagnetic substances and phenomena.
(b) The magnetic property of a paramagnetic substance; that of being
attracted by a magnet, and of arranging itself with its longer axis
parallel with the lines of force of a magnetic field.
Parchmentizing.
If cellulose is treated with a mixture of two parts of sulphuric acid
and one part of water perfectly cold, it becomes like parchment. It
should at once be washed with water, and then with ammonia and water.
The Swan incandescent light fibres are made of parchmentized cotton
thread, which is afterward carbonized.
Partial Earth.
A fault in a conductor caused by imperfect connection with the earth,
where insulation from the earth is desired.
Passive State.
A state of a substance in virtue of which it is unattacked by a solvent
which ordinarily would dissolve or attack it. Iron in strong nitric acid
is unattacked or assumes the passive state. This particular case is
supposed to be due to a coating of magnetic oxide, so that there would
be properly speaking no question of a passive state, but only one of
superficial protection.
The existence of a true passive state of any substance is very doubtful.
P. D.
Abbreviation for potential difference or difference of potential, or for
electro-motive force.