GOLONGAN 2

 

Beryllium

  • X-ray windows (berllium transmits X-rays 17 times better than aluminium
  • as a 2% alloy with nickel for springs, electrodes and nonsparking tools
  • berllium (2%) alloyed with copper gives a hard strong alloy with high resistance to wear used in gyroscopes, computer parts, and instruments (desirable lightness, stiffness)
  • alloys are used as a structural material for high performance aircraft, missiles, spacecraft (such as the USA space shuttle), and communication satellites.
  • ceramics
  • as a moderator in nuclear reactions since it is a highly effective moderator and reflector for neutrons
  • the oxide is used in the nuclear industry

 

Magnesium

  • used in flares and pyrotechnics, including incendiary bombs. It was used in flash photography,
  • it is lighter than aluminium, and is used in alloys used for aircraft, car engine casings, and missile construction
  • it is used a reducing agent for the production of uranium and other metals from their salts
  • the hydroxide (milk of magnesia), chloride, sulphate (Epsom salts), and the citrate are used in medicine
  • magnesium oxide is refractory and used as bricks and liners in furnaces
  • used to make organomagnesium compounds (Grignard reagents), useful in organic synthesis
  • used in computers for radio-frequency shielding

 

Calcium

  • reducing agent for the preparation of metals such as thorium, uranium, zirconium, etc.
  • deoxidiser, desulphurizer, or decarbonizer for various alloys
  • alloys of calcium with agent for aluminium, beryllium, copper, lead, and magnesium have some useful properties
  • “getter” for residual gases in vacuum tubes, etc.
  • quicklime (CaO) is made by heating limestone (CaCO3) and changes into slaked lime, Ca(OH)2, on the addition of water. It is a cheap base for the chemical industry with many uses.
  • calcium from limestone is a component of Portland cement. Mixed with sand it hardens as mortar and plaster while taking up carbon dioxide from the air
  • the solubility of the carbonate in water containing carbon dioxide results in stalactites and stalagmites (Cheddar Gorge) and hardness in water.

 

Strontium

  • fireworks (red flame), flares
  • 90Sr is a radioactive isotope produced by nuclear fallout. 90Sr has the potential for use as lightweight nuclear producing electricity
  • used to produce glass for colour television tubes
  • refining zinc
  • optical materials

 

Barium

  • the sulphate, as permanent white or blanc fixe, is used in paint, in X-ray diagnostic work (BaSO4)
  • glassmaking
  • barite is extensively used as a weighting agent in oil well drilling fluids, and in making rubber
  • the carbonate is a rat poison
  • the nitrate and chlorate give green colours (CARE!) in pyrotechnics
  • sulphide is a white pigment
  • making rubber
  • rat poison

 

Radium

  • self-luminous paints
  • neutron sources
  • medical uses for the treatment of conditions such as cancer (now being replaced by 60Co sources)

 

 

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