Boron Element

About Boron » Boron Element

oron, shown by symbol B in the periodic table, has an atomic number of 5, atomic mass of 10.81, and it is an element in between metal and non-metal having semi conducting property. It is the first and the lightest element of 3A group in the periodic table.

Boron compounds show non-metal properties whereas pure boron shows similar electrical conductivity properties like carbon. Boron crystals look like diamond and nearly as hard as diamond. The basic state electronic configuration of boron is 1s2 2s2 2p1.

Boron element is composed of 8B, 10B, 11B, 12B, 13B isotopes. The most stable isotopes are 10B and 11B. The occurrence of these isotopes in nature are 19.1-20.3 % and  79.7-80.9%,  respectively. 10B isotope shows a very high thermal neutron capture property. Thus, boron can be used in nuclear materials and nuclear energy stations. There are boron reserves rich in 10B isotope ratio in Turkey.

Due to different properties of boron compounds formed with different metal and non-metal elements, boron compounds can be used in different industrial applications.

Boron compounds show different properties when reacted with various metal and non-metal elements that provide them to be used in many industries. Boron behaves as a non-metal in its compounds whereas pure boron is an electricity conductor like carbon. Crystalline boron  looks like diamond in terms of appearance and optical properties and is nearly as hard as diamond.

Pure element of boron was first obtained in 1808 by French chemist J. L. Gay-Lussac and Baron L. J. Thenard and English chemist H. Davy.
Boron is found in various allotropic forms, one being amorphous and six being crystalline polymorphous. Alpha and beta rhombohedral forms are the most studied crystalline polymorhous structures. Alpha rhombohedral structure decomposes above 1200°C and forms beta rhombohedral structure at 1500°C. Amorphous form converts into beta rhombohedral form approximately above 1000°C and all types of pure boron turns into beta rhombohedral form when heated above its melting point and recrystallized.

Boron is the 51st element commonly found in the earth crust. Boron does not occur as a free element in nature. About 230 kinds of boron minerals are known in nature. One of the most commonly found boron mineral in nature is tourmaline which is a kind of aluminoborosilicate mineral and can contain up to 10% of boron. However, tincal (Na4B4O2. 10H2O), kernite (Na2B4O7. 4H2O), colemanite (Ca2B6O11. 5H2O) and ulexite (NaCaB5O9. 8H2O) , which are alkali and alkali earth boron minerals, are used in the industry. The commercial ore reserves are limited and mostly found in Turkey and USA.

The chemical properties of the boron element depend on its morphology and particle size. Micron sized amorphous boron reacts easily and sometimes intensely, whereas crystalline boron does not react easily. Boron reacting with water at high temperature forms boric acid and some other products. The reaction of boron with mineral acids can be slow or explosive depending on the concentration and temperature and boric acid is formed as the main product.