Category
Micro/NanoElectronics
Synonyms
Boron, powder, 45 max. part. size (micron), weight 10 g, purity 98.%; Boron crystalline B GRADE K2 (H.C. STARCK); Boron, monofilament, 0.080 mm diameter, length 100 m; CTK0H8670; Boron 11, 11B, plasma standard solution, Specpure, 11B 100g/ml; Boron Glycinate 5% 40M; Boron amorphous B GRADE II (H.C. STARCK); Boron crystalline B GRADE K1 (H.C. STARCK); Boron, plasma standard solution, Specpure(R), B 1000microg/ml, H3BO3 in 1% NH4OH; Boron powder, crystalline, elec. gr.;
Molecular Weight
10.81g/mol
InChI Key
ZOXJGFHDIHLPTG-UHFFFAOYSA-N;
Melting Point
2,075 deg C;
Density
Amorphous, 2.350 g/cu cm; alpha-rhombohedral, 2.46 g/cu cm; alpha-tetragonal, 2.31 g/cu cm; beta-rhombohedral, 2.35 g/cu cm;
Solubility
Insoluble in water; unaffected by aqueous hydrochloric and hydrofluoric acids; when finely divided it is soluble in boiling nitric and sulfuric acids and in molten metals such as copper, iron, magnesium, aluminum, calcium; reacts vigorously with fused sodium peroxide or with a fusion mixture of sodium carbonate or potassium nitrate;Soluble in concentrated nitric and sulfuric acids; insoluble in water, alcohol, ether;
Application
Boron has found many uses and has become an important industrial chemical. Boron is used as an alloy metal, and when combined with other metals, it imparts exceptional strength to those metals at high temperatures. It is an excellent neutron absorber used to capture neutrons in nuclear reactors to prevent a runaway fission reaction. As the boron rods are lowered into the reactor, they control the rate of fission by absorbing excess neutrons. Boron is also used as an oxygen absorber in the production of copper and other metals, Boron finds uses in the cosmetics industry (talc powder), in soaps and adhesives, and as an environmentally safe insecticide. A small amount of boron is added as a dope to silicon transistor chips to facilitate or impede the flow of current over the chip. Boron has just three valence electrons; silicon atoms have four. This dearth of one electron in boron s outer shell allows it to act as a positive hole in the silicon chip that can be filled or left vacant, thus acting as a type of switch in transistors. Many of today s electronic devices depend on these types of doped-silicon semiconductors and transistors. Boron is also used to manufacture borosilicate glass and to form enamels that provide a protective coating for steel. It is also used as medication for relief of the symptoms of arthritis. Due to boron s unique structure and chemical properties, there are still more unusual compounds to be explored.
Storage
Storage temperature: no restrictions.
Color/Form
Polymorphic: alpha-rhombohedral form, clear red crystals; beta-rhombohedral form, black; alpha-tetragonal form, black, opaque crystals with metallic luster; amorphous form, black or dark brown powder; other crystal forms are known but not entirely characterized;Filaments, powder, whiskers, single crystals;
Covalently-Bonded Unit Count
1
Monoisotopic Mass
11.009g/mol
Other Experimental
Atomic number 5; naturally-occurring isotopes: 10,11; three short-lived artificial isotopes: 8,12, 13;Alpha-rhombohedral form, 12 atoms/unit cell; beta-rhombohedral form, 105 atoms/unit cell; alpha-tetragonal form, 50 atoms/unit cell;The alpha-rhombohedral form of boron is the simplest crystal structure with slightly deformed cubic close packing, which degrades at 1200 deg C and at 1500 it converts to beta-rhombohedral boron, which is the most thermodynamically stable form.;Crystalline boron is very inert. Low purity, higher temperature, and changes in or lack of crystallinity all increase the chemical reactivity.;Boron exists naturally as (10)B (19.9%) and (11)B (80.1%); ten other isotopes of boron are known;Amorphous form, heat capacity: 2.858 cal/g-atom/deg C at 25 deg C; beta-rhombohedral form, heat capacity: 2.650 cal/g-atom/deg C at 25 deg C;Feeble conductor of electricity at room temperature, good conductor at high temperature; self limiting reaction with oxygen due to formation of boric oxide film; oxide coating evaporates above 1000 deg C; crystals are almost as hard as diamond; reacts with fluorine at room temperature;Energy band gap of 1.50-1.56 eV; transmits portions of the infrared;High neutron absorption capacity; amphoteric; Mohs hardness, 9.3;
Physical Description
DryPowder; OtherSolid;
Stability
Fairly stable at normal temperature.;
Topological Polar Surface Area
0A^2
Vapor Pressure
1.56X10-5 atm (0.0119 mm Hg) at 2140 deg C;
Download
Kim, Jun Hee, et al. Nano convergence, 2018, 5(1), 1-13.
Ma, Kang, et al. Thermochimica Acta, 2022, 718, 179368.
