Borax

MINERAL : BORAX

Borax is a white powdery granular substance and a complex borate mineral. Borax is generally described as Na2B4O7·10H2O. It is an important boron compaound, a mineral and a salt of boric acid. It is also known as sodium borate. The basic structure of borax contains chains of interlocking BO2(OH) triangles and BO3(OH) tetrahedrons bonded to chains of sodium and water octahedrons.

OCCURRENCE AND DEPOSITS

Borax is directly deposited in arid regions by the evaporation of water in playas which are intermittent regions of lakes. It is highly concentrated with borons. They are mainly formed during rainy seasons by the runoffs from the mountains. By this process formation of borax takes place. The most commercially important deposits are found in Turkey, Boron, California, and Searles Lake, California. Borax can also be produced synthetically from other boron compounds. Generally the borate beds have been found there underlying between 40 to 300 metres from the surface. The deposits consist of thick beds of kernite and borax. The borax is mainly deposited in USA which produces more than 90% of the total world production. And the other resources of the world are Turkey, Italy, Tibet, Chile, Argentina, Bolivia, USSR.

PROPERTIES

· Color of borax is gray, white, blue and also colourless.
· Its luster varies from Vitreous, Resinous, Earthy.
· Borax is brittle with hardness of 2 to 2.5.
· Fracture is conchoidal.
· Its density is 1.73 g/cm3 .
· Specific Gravity is approximately 1.7.
· It has white streak.
· Borax has the melting point of about 743°C and boiling point of 1575°C. ·



APPLICATIONS/ USES

  • Sodium borate is used in
  • As anti knock agents in gasoline.biochemical and chemical laboratories to make buffers like in gel electrophoresis of DNA.
  • In the field of nuclear energy, boron (the B10 isotope) protects personnel from the harmful effects of reactors. Boron has the unique property of absorbing neutrons produced by nuclear reaction without the emission of harmful secondary gamma radiation.
  • Borax can be used as an additive in ceramic slips and glazes to improve fit on wet, greenware, and bisque.
  • Borax is used as a flux in the manufacture of artificial gems.
  • Cubic boron nitride, commercially called 'Borazon' equals the diamond in hardness and has a greater resistance to oxidation under heat. Borazon can stand the temperature which is more than twice the temperature limit of a diamond i.e. about 900°C.
  • Borax is widely used in glass industry, enamels, cosmetics, food preservatives and pharmaceuticals, pesticides and textile industries.
  • Borax also finds its use in corrosion inhibition, flame proofing.


QUESTION AND ANSWERS

  1. Write the chemical representation of borax?
Ans : Borax is represented as Na2B4O7·10H2O.
  1. How the structure of borax forms?
Ans : The structure of borax contains chains of interlocking BO2(OH) triangles and BO3(OH) tetrahedronsbonded to chains of sodium and water octahedrons.
  1. When and how is borax deposition occurs?
Ans : Borax is directly deposited in arid regions by the evaporation of water in playas which are intermittent regions of lakes. They are formed during rainy seasons by the runoffs from the mountains.
  1. Mention some important prorperties of borax?
Ans : Its luster varies from Vitreous, Resinous, Earthy. Specific Gravity is approximately 1.7.
  1. What are the applications of borax?
Ans : a) Borax is used as a flux in the manufacture of artificial gems.
b) Borax can be used as an additive in ceramic slips and glazes to improve fit on wet, greenware, and bisque.


REFERENCES:

www.wikipedia.com,
www.mineralzone.com
www.mindat.com


PICTURES


Borax - Mineral Process Engineering Borax - Mineral Process Engineering

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