| SYMBOL | B |
|
| ATOMIC NUMBER | 5 |
| ATOMIC WEIGHT | 10.811 |
| GROUP NUMBER | 13 |
| STANDARD STATE | SOLID |
| COLOUR | BLACK |
| DISCOVERED | 1808 BY SIR HUMPHREY DAVEY, GAY-LUSSAC AND THENARD IN ENGLAND AND FRANCE |
| ORIGIN OF NAME | FROM THE ARABICBURAQ AND PERSIAN BURAH |
| USES |
- AMORPHOUS BORON IS USED IN PYROTECHNIC FLARES DUE TO ITS DISTINCTIVE GREEN COLOUR
- BORIC ACID IS USED AS A MILD ANTISEPTIC.
- BORAX (Na2B4O7.10H2O)IS USED AS A CLEANING FLUX IN WELDING AND AS A WATER SOFTNER IN WASHING POWDERS
- IN THE PRODUCTION OF ENAMALS TO COAT STEEL
- BORON COMPOUNDS ARE USED IN GLASS PRODUCTION AND IN ANTI-ARTHRITIS DRUGS
- A BORON ISOTOPE IS USED AS CONTROL RODS FOR NUCLEAR REACTORS, RADIATION SHIELDS AND NEUTRON DETECTING INSTRUMENTS
- BORON HYDRIDES ARE USED AS ROCKET FUELS
- FILAMENTS FOR AEROSPACE STRUCTURES AS IS IS LIGHT BUT STRONG
- FIBRE OPTICS RESEARCH
|
| ATOMIC RADIUS | 0.83 * 10-10M |
| COMPOUNDS |
- B203, H3BO3, NaBH4, BeF3, BCl3, BORATES AND BORANES
- BORON NITRIDE IS AS HARD AS DIAMOND, CONDUCTS HEAT BUT IS AN ELECTRICAL INSULATOR AS WELL AS LUBRICATING LIKE GRAPHITE
|
| EFFECTIVE NUCLEAR CHARGE (Slater) | 2.60 |
| DENSITY | 2340 KgM-3 |
| MELTING POINT | 2573 K |
| BOILING POINT | 3931 K (UNDER PRESSURE) |
| ENTHALPY OF FUSION | 22.2 KJMol-1 |
| ENTHALPY OF VAPOURISATION | 538.9 KJMol-1 |
| ISOTOPES | B-8, B-9, B-10, B-11, B-10, B-11, B-12, B-13 ALL RADIOACTIVE EXCEPT B-10 AND B-11 |
| ELECTRON CONFIGURATION | 1S22S22P1 |
| FIRST IONISATION ENERGY | 800.6 KJMol-1 |
| ELECTRON AFFINITY | 26.7 KJMol-1 |
| SOURCES | MINED IN U.S.A., TIBET, CHILE AND TURKEY |
| GENERAL INFORMATION | BORON IS ON THE BORDERLINE BETWEEN METALS ANS NON METALS AND SO IS A SEMI CONDUCTOR. IN ITS CRYSTALLINE FORM IT IS MOSTLY INERT |
BORON