Desember 2011 - Jejaring Kimia


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Desember 19, 2011

Beryllium [Be]

Desember 19, 2011 1


An: 4 N: 5
Am: 9.012182 (3) g/mol
Group No: 2
Group Name: Alkaline earth metal
Block: s-block Period: 2
State: solid
Colour: lead grey Classification: Metallic
Boiling Point: 2742K (2469°C)
Melting Point: 1560K (1287°C)
Superconducting temperature: 0.026K (-273.124°C)
Density: 1.85g/cm3

Discovery Information

Who: Fredrich Wöhler, A. A. Bussy
When: 1798
Where: Germany/France

Name Origin

From the mineral beryl. "Beryllium" in different languages.


Found mostly in minerals like beryl [AlBe3(Si6O18)] and chrysoberyl (Al2BeO4).
Important mining locations are Brazil, the USA, Madagascar, Germany, Czech Republic, Russia and India. Annual production is round 360 tons. Total world-wide reservers are estimate to be around 400 thousand tons.


Universe: 0.001 ppm (by weight)
Sun: 0.0001 ppm (by weight)
Carbonaceous meteorite: 0.03 ppm
Earth’s Crust: 2.6 ppm
Seawater: Atlantic surface: 8.8 x 10-8 ppm; Atlantic deep: 1.7 x 10-7 ppm; Pacific surface: 3.5 x 10-8 ppm; Pacific deep: 2.2 x 10-7 ppm
Human: 0.4 ppb by weight; 0.3 ppb by atoms


Its ability to absorb large amounts of heat makes it useful in spacecraft, missiles, aircraft, etc. Emeralds are beryl crystals with chromium traces giving them their green colour. Also used in light weight metal alloys, X-ray tube windows, watch springs and sparkless tools.

Beryllium oxide (BeO) is useful for many applications that require an excellent heat conductor, with high strength and hardness, with a very high melting point, and that acts as an electrical insulator.

Beryllium is also used in the making of gyroscopes, various computer equipment, watch springs and instruments where light-weight, rigidity and dimensional stability are needed.

The James Webb Space Telescope, will have 18 hexagonal beryllium sections for its mirrors. Because the JWST will face a temperature of -240 degrees Celsius (30 kelvins), the mirror is made of beryllium, a material capable of handling extreme cold better than glass. Beryllium contracts and deforms less than glass, and thus remains more uniform, in such temperatures.


This element was discovered by Louis Vauquelinin 1798 as the oxide in beryl and in emeralds. Friedrich Wöhler and A. A. Bussy independently isolated the metal in 1828 by reacting potassium and beryllium chloride.


The speed of sound in beryllium (12,500 m s-1) is greater than in any other element.

Beryllium comes from Greek beryllos, beryl. It has also been called Glucinium or Glucinum from the Greek word glykys which means "sweet." Beryllium is found in beryl, chrysoberyl (Al2BeO4) and phenakite (Be2SiO4). Aquamarine and emeralds are precious forms of beryl. It has a high melting point for a light metal and is more elastic than steel. It is used in computer parts, gyroscopes and for construction. Beryllium and its salts are toxic and should be handled with great care. Do not taste it to confirm that it is sweet.

Beryllium is an essential constituent of roughly 100 out of about 4000 known minerals.


Beryllium and its salts are highly toxic substances and carcinogenic.

Beryllium Compounds

Beryllium oxide BeO : Carcinogenic :
Beryllium oxide is used in many high-performance semiconductor parts for applications such as radio equipment because it has good thermal conductivity while also being a good electrical insulator. It is also used as a structural ceramic for high-performance vacuum tubes, magnetrons, and gas lasers.

Reactions of Beryllium

Reactions with water
Beryllium will not react with water (or steam) even if heated.
Reactions with air
The surface of beryllium metal is covered with a thin layer of oxide that helps protect the metal from attack by air. It does not oxidize in air even at 600°C. Powdered beryllium metal does burn in air to give a mixture of white beryllium oxide, BeO, and beryllium nitride, Be3N2.
2Be(s) + O2(g) --> 2BeO(s)
3Be(s) + N2(g) --> 2Be3N2(s)
Reactions with halogens
Beryllium metal reacts chlorine, Cl2, or bromine, Br2, to form the beryllium dihalides; beryllium(II) chloride, BeCl2, and beryllium(II) bromide, BeBr2, respectively.
Be(s) + Cl2(g) --> BeCl2(s)
Be(s) + Br2(g) --> BeBr2(s)
Reactions with acids
The surface of beryllium metal is covered with a thin layer of oxide that helps protect the metal from attack by acids, but powdered beryllium metal dissolves readily in dilute acids such as sulphuric acid, hydrochloric acid, or nitric acid to form solutions containing the aquated Be(II) ion together with hydrogen gas, H2.
Be(s) + H2SO4(aq) --> Be2+(aq) + SO42-(aq) + H2(g)
Reactions with bases
Beryllium metal dissolves readily in dilute aquesous base solutions such as sodium hydroxide, NaOH, to form Be(II) complexes together with hydrogen gas, H2.

Occurrence and Production of Beryllium

Natural Abundance
Beryllium is an essential constituent of about 100 out of about 4000 known minerals, the most important of which are bertrandite (Be4Si2O7(OH)2), beryl (Al2Be3Si6O18), chrysoberyl (Al2BeO4), and phenakite (Be2SiO4). Precious forms of beryl are aquamarine and emerald.

The most important commercial sources of beryllium and its compounds are beryl and bertrandite. Beryllium metal did not become readily available until 1957. Currently, most production of this metal is accomplished by reducing beryllium fluoride with magnesium metal. The price on the US market for vacuum-cast beryllium ingots was 338 US$ per pound ($745/kg) in 2001.
BeF2 + Mg --> MgF2 + Be

Isotopes of Beryllium

7Be [3 neutrons]
Abundance: synthetic
Half life: 53.12 days [ Electron Capture ]
Decay Energy: ? MeV
Decays to 7Li.
Half life: 53.12 days [ Gamma Radiation ]
Decay Energy: 0.477 MeV
Decays to ?. 

9Be [5 neutrons]
Abundance: 100%
Stable with 5 neutron 

10Be [6 neutrons]
Abundance: trace
Half life: 1.51 x 106 years [ beta- ]
Decay Energy: 0.556 MeV
Decays to 10B. 

Cosmogenic 10Be is produced in the atmosphere by cosmic ray spallation of oxygen and nitrogen.
10Be and its daughter products have been used to examine soil erosion, soil formation from regolith, the development of lateritic soils, as well as variations in solar activity and the age of ice cores. It is also formed in nuclear explosions by a reaction of fast neutrons with 13C in the carbon dioxide (CO2) in air, and is one of the historical indicators of past activity at nuclear test sites.
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Rino Safrizal
Jejaring Kimia Updated at: Desember 19, 2011

BERYL [ Silicates : Cyclosilicates ]

Desember 19, 2011 0
Be3Al2(SiO3)6, Berylium aluminium Silicate: Gemstone, mineral specimens and source of beryllium

Beryl is often unknown to the general public, even the gemstone-buying public. However, it is one of the most important gem minerals. Beryl is colourless in pure form; it is the many different impurities that give beryl its varied colouration. Without these splendid colour varieties, beryl would be a rather ordinary gemstone with only average fire and brilliance. Emerald is the green variety and aquamarine is the blue variety of beryl.

emerald is highly prized and is one of the most valued gemstones. Its green colour is peerless and all other green gemstones are compared to its intensity. Emerald specimens are often "flawed" with mineral inclusions and fractures; unlike other gems, these are considered part of the stones’ "character." These flaws actually help determine natural from synthetically-produced stones. Uncut emerald specimens are rare on the mineral markets, probably because even low grade emeralds can carry a high price when cut as gems. Especially hard to find are true "in-matrix" specimens. Fakes are often produced with natural crystals glued into a "host" rock and then sold as an in-matrix specimen with a highly inflated price.

aquamarine is also a popular gem although it does not command nearly as high a price as its green cousin. Uncut aquamarines are plentiful but relatively expensive, as would be expected of crystalline gemstone specimens. Large crystals of aquamarine are available on the open market and represent perhaps the largest raw gemstone specimens.

Physical Characteristics

Colour: varied and includes emerald green, blue to blue-green, yellow, greenish-gold, red, colourless and pink
Luster: vitreous
Transparency: Crystals are transparent to translucent
Crystal System: hexagonal; 6/m 2/m 2/m
Crystal Habits: typically include the hexagonal prism with pincoid terminations. The terminations are often modified by many different pyramidal faces which can sometimes produce a rounded termination in the rough shape of a used pencil eraser
Cleavage: imperfect in one direction (basal)
Fracture: conchoidal
Hardness: 7.5 - 8
Specific Gravity: approx. 2.6 - 2.9 (average)
Streak: white
Other: Faces on large crystals are often pitted, striated lengthwise and rough
Associated Minerals: include micas, quartz, euclase, calcite, tourmalines and some feldspars
Major Occurrences: include Colombia and some African localities for emerald; Brazil, Russia and Pakistan for aquamarine; California, Brazil, Africa, and many other localities for other beryls
Best Indicators: crystal habit, lack of good cleavage, hardness and colour
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Rino Safrizal
Jejaring Kimia Updated at: Desember 19, 2011

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