Boron

elementong kimikal, simbolong B at atomikong bilang 5

Ang boro (Ingles: boron) ay isang elementong kimikal sa talahanayang peryodiko na sinasagisag ng simbolong B at nagtataglay ng atomikong bilang 5.

Boron, 5B
boron (β-rhombohedral)[1]
Boron
Pronunciation /ˈbɔːrɒn/ (BOR-on)
Allotropesα-, β-rhombohedral, β-tetragonal (at marami pa)
Appearanceblack-brown
Standard atomic weight Ar°(B)
  • [10.80610.821]
  • 10.81±0.02 (pinaikli)[2][3]
Boron in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


B

Al
berylliumboroncarbon
Atomic number (Z)5
Group13
Period2
Block  p-block
Electron configuration[He] 2s2 2p1
Electrons per shell2, 3
Physical properties
Phase at STPsolido
Melting point2349 K ​(2076 °C, ​3769 °F)
Boiling point4200 K ​(3927 °C, ​7101 °F)
Density when liquid (at m.p.)2.08 g/cm3
Heat of fusion50.2 kJ/mol
Heat of vaporization508 kJ/mol
Molar heat capacity11.087 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2348 2562 2822 3141 3545 4072
Atomic properties
Oxidation states−5, −1, 0,[4] +1, +2, +3[5][6] (isang katamtamang asidikong oksido)
ElectronegativityPauling scale: 2.04
Ionization energies
  • 1st: 800.6 kJ/mol
  • 2nd: 2427.1 kJ/mol
  • 3rd: 3659.7 kJ/mol
  • (more)
Atomic radiusempirical: 90 pm
Covalent radius84±3 pm
Van der Waals radius192 pm
Color lines in a spectral range
Mga linyang espektral ng boron
Other properties
Natural occurrenceprimordiyal
Crystal structurerhombohedral
Rhombohedral crystal structure for boron
Thermal expansionβ form: 5–7 µm/(m⋅K) (at 25 °C)[7]
Thermal conductivity27.4 W/(m⋅K)
Electrical resistivity~106 Ω⋅m (at 20 °C)
Magnetic orderingdiamagnetic[8]
Molar magnetic susceptibility−6.7×10−6 cm3/mol[8]
Speed of sound thin rod16,200 m/s (at 20 °C)
Mohs hardness~9.5
CAS Number7440-42-8
History
DiscoveryJoseph Louis Gay-Lussac and Louis Jacques Thénard[9] (30 June 1808)
First isolationHumphry Davy[10] (9 July 1808)
Isotopes of boron
Main isotopes Decay
abun­dance half-life (t1/2) mode pro­duct
8B synth 771.9 ms β+ 8Be
10B 19.6% stable
11B 80.3% stable
Kategorya Kategorya: Boron
| references

May atomikong bigat na 10.118, punto ng pagkatunaw na 2,300oC, nagkakaroon ng sublimasyon sa 2,550oC, may espesipikong grabidad na 2.34 (anyong kristalina), at balensiyang 3) ay isang hindi metalikong elemento na malambot at kakulay ng kape, at nasa anyong amorpus o kristalina. Nakukuha ang mga ito mula sa kerito at boraks. Naihiwalay ito nina Humphry Davy, Joseph Louis Gay-Lussac at Louis Jacques Thénard[11] noong 1808 sa pamamagitan ng reaksiyon ng asidong boriko at ng potasyo. Tinawag ito ni Davy bilang boracium.[12] Nagagamit ang elementong ito para sa paggawa ng mga pampasibad na kemikal, sa mga pampailaw, panggasgas, at maging para sa aloy na matitigas.[11]

Mga sanggunian

baguhin
  1. Van Setten et al. 2007, pp. 2460–1
  2. "Standard Atomic Weights: Boron" (sa wikang Ingles). CIAAW. 2009.{{cite web}}: CS1 maint: date auto-translated (link)
  3. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry (sa wikang Ingles). doi:10.1515/pac-2019-0603. ISSN 1365-3075.{{cite journal}}: CS1 maint: date auto-translated (link)
  4. Braunschweig, H.; Dewhurst, R. D.; Hammond, K.; Mies, J.; Radacki, K.; Vargas, A. (2012). "Ambient-Temperature Isolation of a Compound with a Boron-Boron Triple Bond". Science (sa wikang Ingles). 336 (6087): 1420–2. Bibcode:2012Sci...336.1420B. doi:10.1126/science.1221138. PMID 22700924. S2CID 206540959.{{cite journal}}: CS1 maint: date auto-translated (link)
  5. Zhang, K.Q.; Guo, B.; Braun, V.; Dulick, M.; Bernath, P.F. (1995). "Infrared Emission Spectroscopy of BF and AIF" (PDF). J. Molecular Spectroscopy (sa wikang Ingles). 170 (1): 82. Bibcode:1995JMoSp.170...82Z. doi:10.1006/jmsp.1995.1058.{{cite journal}}: CS1 maint: date auto-translated (link)
  6. Melanie Schroeder. Eigenschaften von borreichen Boriden und Scandium-Aluminium-Oxid-Carbiden (PDF) (sa wikang Ingles). p. 139.
  7. Holcombe Jr., C. E.; Smith, D. D.; Lorc, J. D.; Duerlesen, W. K.; Carpenter; D. A. (Oktubre 1973). "Physical-Chemical Properties of beta-Rhombohedral Boron". High Temp. Sci. 5 (5): 349–57.{{cite journal}}: CS1 maint: date auto-translated (link)
  8. 8.0 8.1 Haynes, William M., pat. (2016). CRC Handbook of Chemistry and Physics (ika-97th (na) edisyon). CRC Press. p. 4.127. ISBN 9781498754293.{{cite book}}: CS1 maint: date auto-translated (link)
  9. Gay Lussac, J.L.; Thenard, L.J. (1808). "Sur la décomposition et la recomposition de l'acide boracique". Annales de chimie. 68: 169–174.{{cite journal}}: CS1 maint: date auto-translated (link)
  10. Davy H (1809). "An account of some new analytical researches on the nature of certain bodies, particularly the alkalies, phosphorus, sulphur, carbonaceous matter, and the acids hitherto undecomposed: with some general observations on chemical theory". Philosophical Transactions of the Royal Society of London. 99: 39–104. doi:10.1098/rstl.1809.0005.{{cite journal}}: CS1 maint: date auto-translated (link)
  11. 11.0 11.1 Gaboy, Luciano L. Boron - Gabby's Dictionary: Praktikal na Talahuluganang Ingles-Filipino ni Gabby/Gabby's Practical English-Filipino Dictionary, GabbyDictionary.com.
  12. Weeks, Mary Elvira (1933). "XII. Other Elements Isolated with the Aid of Potassium and Sodium: Beryllium, Boron, Silicon and Aluminum". The Discovery of the Elements. Easton, PA: Journal of Chemical Education. ISBN 0-7661-3872-0.{{cite book}}: CS1 maint: date auto-translated (link)