Boron
- amorphous boron is used in
pyrotechnic flares (distinctive green colour), and rockets (as an igniter)
- boric, or boracic, acid, is
used as a mild antiseptic
- borax, Na2B4O7.10H2O,
is a cleansing flux in welding
- borax, Na2B4O7.10H2O
is a water softener in washing powders
- boron compounds are used in
production of enamels for covering steel of refrigerators, washing
machines, etc.
- boron compounds are extensively
used in the manufacture of enamels and borosilicate glasses
- boron compounds show promise in
treating arthritis
- 10B is used as a control for nuclear reactors, as a
shield for nuclear radiation, and in instruments used for detecting
neutrons
- boron nitride is as hard as
diamond. It behaves like an electrical insulator, but conducts heat like a
metal. It also has lubricating properties similar to graphite
- the hydrides are sometimes used
as rocket fuels
- boron filaments, a
high-strength, lightweight material, are used for advanced aerospace
structures, .
- lightweight compounds used for
aerospace structures
- boron filaments used in fibre
optics research
- Boric Acid is also used in
North America for the control of cockroaches, silverfish, ants, fleas, and
other insects.
Aluminium
- cans and foils
- kitchen utensils
- outside building decoration
- industrial applications where a
strong, light, easily constructed material is needed
- although its electrical
conductivity is only about 60% that of copper per area of cross section,
it is used in electrical transmission lines because of its lightness and
price
- alloys are of vital importance
in the construction of modern aircraft and rockets
- aluminium, evaporated in a
vacuum, forms a highly reflective coating for both visible light and
radiant heat. These coatings soon form a thin layer of the protective
oxide and do not deteriorate as do silver coatings. These coatings are
used for telescope mirrors, decorative paper, packages, toys, and in many
other uses
- the oxide, alumina, occurs
naturally as ruby, sapphire, corundum, and emery, and is used in glass
making and refractories. Synthetic ruby and sapphire are used in the
construction of lasers
Gallium
- gallium wets glass or
porcelain, and forms a brilliant mirror when it is painted on glass
- used for doping semiconductors
and producing solid-state devices such as transistors
- gallium arsenide converts
electricity into coherent light
- alloying
- 90 tons of gallium (2 or 3
years of world production) is used to detect solar neutrinos by the use of
the reaction: nu + 71Ga > 71Ge + e-.
The rate, although very low (less than 1 interaction per day in 30 tonnes
of Ga) makes gallium unique for this purpose. Two experiments are running
: - GALLEX using 30 tons in the Gran Sasso underground laboratory (Italy)
and SAGE with 60 tons in the Baksan laboratory in Caucasus (Russia).
[thanks Michel]
Indium
- 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 those made with silver,
but with more resistance to atmospheric corrosion
- photocells
- used to make low-melting
alloys, alloyed with gallium
- indium is used in solders
Thallium
- the sulphate was widely used as
a rodenticide and ant killer. It is odourless and tasteless, giving no
warning of its presence
- the electrical conductivity of
thallium sulphide changes with exposure to infrared light, and so it is
used in photocells
- thallium bromide-iodide
crystals are used as infrared detectors
- used, with sulphur or selenium
and arsenic, to produce low melting glasses which become fluid between 125
and 150°C
- originally used in treating
ringworm and other skin infections. Its use was limited because of the
narrow margin between toxicity and therapeutic benefits
- A mercury-thallium alloy, which
forms a eutectic at 8.5% thallium, freezes at -60°C, some 20° below the
freezing point of mercury
Ununtrium
- Element 113 has no uses as only a very few atoms of this element have been identified.
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