In
INDIUM
(from the brilliant indigo line in its spectrum)
In at. wt. 114.82
at. no. 49
m.p. 156.61°C
b.p. 2080°C
sp. gr. 7.31 (20°C)
valence 1, 2, or 3.
Electronic configuration
| SHELL |
K |
L |
M |
N |
O |
P |
Q |
| SUB SHELL |
He |
Neon |
Argon |
Krypton |
Xenon |
Radon |
Eka-radon |
| 1s |
2s 2p |
3s 3p |
3d 4s 4p |
4d 5s 5p |
4f 5d 6s 6p |
5f 6d 7s 7p |
| Indium
|
1s22s22p63s23p63d104s24p64d105s25p1 |
|
|
| Symbol
|
2P½ |
Indium was discovered by Reich
and Richter, who later isolated the metal. Indium is most
frequently associated with zinc minerals, and it is from these
that most commercial indium is now obtained; however,
it is also found in iron, lead, and copper ores. Until 1924, a
gram or so constituted the world's supply of this element in
isolated form. It is probably about as abundant as silver.
One to 1 + million troy ounces of indium are now produced
annually in the Free World. Japan is presently producing
more thari 250,000 troy oz. annually. The present cost of
indium is about $1.50 to $5.00/troy oz., depending on
quantity and purity. It is available in ultrapure form.
Indium is a very soft, silvery-white metal with a brilliant
luster. The pure metal gives a high-pitched "cry" when
bent. It wets glass, as does gallium. It has found application
in making low-melting alloys; an alloy of 24% indium-76 %
gallium is liquid at room temperature. It is used in making
bearing alloys, germanium transistors, rectifiers, thermistors,
and photoconductors. It can be plated onto metal and
evaporated onto glass forming a mirror as good as that made
with silver, but with more resistance to atmospheric cor-
rosion. There is evidence that indium has a low order of
toxicity. Normal hygienic precautions should provide ade-
quate protection.

© 1999 F. Davies
Delphi O.E.M. Co.
All rights reserved