Boron

Boron (B)


 * Name:** Boron
 * Symbol:** B
 * Atomic Number:** 5
 * Atomic Mass:** 10.811 amu
 * Melting Point:**2300.0 °C (2573.15 K, 4172.0 °F)
 * Boiling Point:** 2550.0 °C (2823.15 K, 4622.0 °F)
 * Number of Protons/Electrons:** 5
 * Number of Neutrons:** 6
 * Classification:** Metalloid
 * Crystal Structure:** Rhombohedral
 * Density @ 293 K:** 2.34 g/cm 3
 * Color:** brownish

Common Facts
Boron is a metalloid and has properties of both metals and non metal and is not found in a __free__state in nature. Boron is produced by cosmic rat spallation, and contrary to popular belief, it is not created by stellar nucleosynthesis. This element is of low abundance in the Earth's crust and in the atmosphere. It is used for the production of glass and ceramics. Boron is a also a rare element in the Earth's crust, at only 0.001% and 72% of that is in Turkey. Boric acid can be found in hot springs or near volcanoes. Boron is atomic number 5.

boron is a Group 13 element that has properties which are (semimetallic) as stated above. It is a semiconductor rather than a metallic conductor. Chemically it is closer to silicon than to aluminium, gallium, indium, and thallium. Crystalline boron is inert chemically and is resistant to attack by boiling HF or HCl. When finely divided it is attacked slowly by hot concentrated nitric acid.

Boron was discovered by Joseph-Louis Gay-Lussac and Louis-Jaques Thénard, French chemists, and independently by Sir Humphry Davy, an English chemist, in 1808. They all isolated boron by combining boric acid (H3BO3) with potassium. Today, boron is obtained by heating borax (Na 2 B 4 O 7 ·10H 2 O) with carbon, although other methods are used if high-purity boron is required. Boron is used in pyrotechnics and flares to produce a green color. Boron has also been used in some rockets as an ignition source. Boron-10, one of the naturally occurring isotopes of boron, is a good absorber of neutrons and is used in the control rods of nuclear reactors, as a radiation shield and as a neutron detector. Boron filaments are used in the aerospace industry because of their high-strength and lightweight. Boron forms several commercially important compounds. The most important boron compound is sodium borate pentahydrate (Na 2 B 4 O 7 ·5H 2 O). Large amounts of this compound are used in the manufacture of fiberglass insulation and sodium perborate bleach. The second most important compound is boric acid (H 3 BO 3 ), which is used to manufacture textile fiberglass and is used in cellulose insulation as a flame retardant. Sodium borate decahydrate (Na 2 B 4 O 7 ·10H 2 O), better known as borax, is the third most important boron compound. Borax is used in laundry products and as a mild antiseptic. Borax is also a key ingredient in a substance known as Oobleck, a strange material 6th grade students experiment with while participating in Jefferson Lab's BEAMS program. Other boron compounds are used to make borosilicate glasses, enamels for covering steel and as a potential medicine for treating arthritis. It is very useful when covering steel to make it stronger. Boron has two isotopes that are naturally occurring and stable.
 * History and Uses:**


 * || **Atomic number** || 5 ||
 * **Atomic mass** || 10.81 g.mol -1 ||
 * **Electronegativity according to Pauling** || 2.0 ||
 * **Density** || 2.3 g.cm-3 at 20°C ||
 * **Melting point** || 2076 °C ||
 * **Boiling point** || 3927 °C ||
 * **Vanderwaals radius** || 0.098 nm ||
 * **Ionic radius** || 0.027 nm ||
 * **Isotopes** || 2 ||
 * **Electronic shell** || [ He ] 2s22p1 ||
 * **Energy of first ionisation** || 800.5 kJ.mol -1 ||
 * **Energy of second ionisation** || 2426.5 kJ.mol -1 ||
 * **Energy of third ionisation** || 3658.7 kJ.mol -1 ||
 * **Discovered by** || Sir Humphry Davy and J.L Gay-Lussac in 1808 ||  ||

Read more: http://www.lenntech.com/periodic/elements/b.htm#ixzz1oGy5vQB3  
 * Chemical Symbol: ||  || B ||
 * Atomic Number: ||  || 5 ||
 * Atomic Weight: ||  || 10.81 ||
 * Melting Point: ||  || 2030 °C ||
 * Boiling Point: ||  || 3700 °C ||
 * Density of Solid: ||  || 2466 kg m-3 ||
 * Electron Configuration: ||  || 1s2 2s2 2p1 ||


 * Symbol:** B **Atomic Number:** 5 **Atomic Mass:** 10.811 amu **Melting Point:** 2300.0 °C (2573.15 K, 4172.0 °F) **Boiling Point:** 2550.0 °C (2823.15 K, 4622.0 °F) **Number of Protons/Electrons:** 5 **Number of Neutrons:** 6 **Classification:** Metalloid **Crystal Structure:** Rhombohedral **Density @ 293 K:** 2.34 g/cm3 **Color:** brownish


 * [[image:http://www.chemicalelements.com/bohr/b0005.gif width="213" height="211"]] ||  || **Number of Energy Levels:** 2
 * First Energy Level:** **Second Energy Level:** ||


 * ** Isotope ** || ** Half Life ** ||
 * B-10 || Stable ||
 * B-11 || Stable ||


 * Date of Discovery:** 1808 **Discoverer:** Sir Humphry Davy, J.L Gay-Lussac **Name Origin:** From borax and carbon **Uses:** heat resistant alloys **Obtained From:** kernite

Abundance

 * [|Amount in average human body (70kg):] ||  || 0.048 g ||
 * Average amount in Earth's crust: ||  || 10 ppm by mass ||
 * [|Average amount in seawater:] ||  || 4.4 mg L-1

Magnets

Boron is a component of neodymium magnets (Nd2Fe14B), which are the strongest type of permanent magnet. They are found in a variety of domestic and professional electromechanical and electronic devices, such as magnetic resonance imaging (MRI), various motors and actuators, computer HDDs, CD and DVD players, mobile phones, timer switches, speakers, and so on.[2home] ||