Tuesday, 11 September 2012


Oxygen [O]
CAS-ID: 7782-44-7
An: 8 N: 8
Am: 15.9994 (3) g/mol
Group No: 16
Group Name: Chalcogen
Block: p-block Period: 2
State: gas at 298 K
Colour: colourless as a gas, liquid is pale blue Classification: Non-metallic
Boiling Point: 90.2K (-182.9°C)
Melting Point: 54.8K (-218.3°C)
Critical temperature: 154.6K (-118.5°C)
Density: 1.429g/l

Discovery Information
Who: Joseph Priestley, Karl Wilhelm Scheele
When: 1774
Where: England/Sweden

Name Origin
Greek: oxus (acid) and gennan (generate).

Obtained primarily from by liquification and then fractional distillation of the air. World wide production is around 100 million tons.

Universe: 10000 ppm (by weight)
Sun: 9000 ppm (by weight)
Carbonaceous meteorite: 4.1 x 105 ppm
Atmosphere: 2.095 x 105 ppm
Earth's Crust: 4.74 x 105 ppm
6.1 x 108 ppb by weight
2.4 x 108 ppb by atoms

Used in steel making, production of methanol (CH3OH), welding, water purification, cement and rocket propulsion. It is also required for supporting life and combustion. Oxygen is a major component of air, produced by plants during photosynthesis, and is necessary for aerobic respiration in animals.

Oxygen was first described by Michal Sedziwoj, a Polish alchemist and philosopher in the late 16th century. Sedziwoj thought of the gas given off by warm niter (saltpeter) as "the elixir of life".

Oxygen was more quantitatively discovered by the Swedish pharmacist Karl Wilhelm Scheele some time before 1773, but the discovery was not published until after the independent discovery by Joseph Priestley on August 1, 1774, who called the gas dephlogisticated air. Priestley published discoveries in 1775 and Scheele in 1777; consequently Priestley is usually given the credit. Both Scheele and Priestley produced oxygen by heating mercuric oxide.

Scheele called the gas 'fire air' because it was the only known supporter of combustion. It was later called 'vital air' because it was and is vital for the existence of animal life.

The gas was named by Antoine Laurent Lavoisier, after Priestley's publication in 1775, from Greek roots meaning "acid-former". As noted, the name reflects the then-common incorrect belief that all acids contain oxygen. This is also the origin of the Japanese name of oxygen "sanso" (san=acid, so=element).

Oxygen was first time condensed in 1883 by professors of Jagiellonian University - Zygmunt Wroblewski (Polish chemist) Karol Olszewski (Polish physicist and chemist).

Liquid and solid O2 are both a light blue colour. Ozone (O3) is a deeper blue colour. Oxygen is the second most common element on Earth, composing around 46% of the mass of Earth's crust (the most common element) and 28% of the mass of Earth as a whole, and is the third most common element in the universe. Forms almost 21% of atmosphere.

Certain derivatives of oxygen, such as ozone (O3), singlet oxygen, hydrogen peroxide (H2O2), hydroxyl radicals and superoxide (O2-), are highly toxic. Highly concentrated sources of oxygen promote rapid combustion and therefore are fire and explosion hazards in the presence of fuels.

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Thursday, 8 March 2012

Lowongan Kerja Pertamina 2012

Meski agak terlambat memposting info ini, mudah-mudahan tidak menjadi soal. Sebuah perusahaan Migas tentunya menjadi idaman setiap orang untuk bisa mengapresiasikan diri di sana. Nah, tahun ini, tepatnya bulan Februari - Maret ini, Pertamina membuka kesempatan karir bagi siapa saja untuk menjadi bagian dari mereka untuk mampu menjawab tantangan jaman di perminyakan.

Lowongan Kerja Pertamina Tahun 2012 inipun dibuka secara online. Sehingga siapapun dapat mendaftarkan diri sesuai dengan kualifikasi pendidikan yang ada.

Untuk Lulusan Baru
PosisiExpired DateDetil Posisi
BPA (D3) Ekonomi & Management 15/03/2012 Klik Disini
BPA (D3) Teknik 15/03/2012 Klik Disini
BPA (D3) MIPA/Sains 15/03/2012 Klik Disini
BPS (S1) Teknik 15/03/2012 Klik Disini
BPS (S1) Sosial Politik/Komunikasi 15/03/2012 Klik Disini
BPS (S1) MIPA/Sains 15/03/2012 Klik Disini
BPS (S1) Ilmu Komputer/Sistem Informasi 15/03/2012 Klik Disini
BPS (S1) Hukum 15/03/2012 Klik Disini
BPS (S1) Psikologi 15/03/2012 Klik Disini
BPS (S1) Ekonomi/Management/Business 15/03/2012 Klik Disini

Untuk Berpengalaman
PosisiExpired DateDetil Posisi
Jr. Attorney 09/03/2012 Klik Disini
Analyst Cost Control 09/03/2012 Klik Disini
Specialist Contract and Procurement 09/03/2012 Klik Disini
Superintendent Technical Maintenance 09/03/2012 Klik Disini
Supervisor Automation 09/03/2012 Klik Disini
Officer C&B 09/03/2012 Klik Disini

Atau bisa langsung kunjungi web nya di

Semoga informasi ini bermanfaat buat teman-teman semua. Selamat Berjuang Sahabat...!!!!!

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Friday, 18 November 2011


Nitrogen [N]
CAS-ID: 7727-37-9
An: 7 N: 7
Am: 14.0067 g/mol
Group No: 15
Group Name: Pnictogen
Block: p-block Period: 2
State: gas at 298 K
Colour: colourless Classification: Non-metallic
Boiling Point: 77.36K (-195.79°C)
Melting Point: 63.05K (-210.1°C)
Critical temperature: 126.2K (-146.9°C)
Density: 1.251g/l

Discovery Information
Who: Daniel Rutherford
When: 1772
Where: Scotland/Sweden

Name Origin
Latin nitrogenium, where nitrum (from Greek nitron) means "native soda", and genes means "forming".

Nitrogen can be made by liquification and then fractional distillation of the air. It is very easily done commercially. It can also be made by heating NaN3 to 300 degrees C. Around 44 million tons are produced annually.

Universe: 1000 ppm (by weight)
Sun: 1000 ppm (by weight)
Carbonaceous meteorite: 1400 ppm
Earth's Crust: 25 ppm

Atlantic surface: 8 x 10-5 ppm
Atlantic deep: 2.7 x 10-1 ppm
Pacific surface: 8 x 10-5 ppm
Pacific deep: 5.4 x 10-1 ppm

2.6 x 107 ppb by weight
1.2 x 107 ppb by atoms

Nitrogen has many industrial uses in the gaseous forms, but probably the most interesting is liquid nitrogen, which is extremely cold. Items that must be frozen to extremely low temperatures for preservation are frequently stored in liquid nitrogen. Fertility clinics store sperm, eggs and embryos used to help infertile couples become pregnant in ampoules in liquid nitrogen. Since nitrogen gas is very stable, at standard temperature and pressure, it is used as the air in inert welding atmospheres. Documents, foods and chemicals are sometimes stored in nitrogen to keep them from oxidizing or reacting with air or water.

Nitrogen is the largest single component of the Earth's atmosphere (78.084% by volume, 75.5% by weight).

Nitrogen in the elemental form was considered to be inert and was even named ozote which refers to the fact that it is not reactive. Of course nitrogen does form compounds, but the gaseous form consists of diamers (2 nitrogens bonded together). The diamer is very stable.

Nitrogen is a major element in organic compounds, especially proteins. Some nitrogen compounds are highly reactive. Trinitrotoluene is TNT or dynamite. Ammonium Nitrate is a fertilizer, but was used as the major explosive ingredient in the Oklahoma City bombing. Anfo, or Ammonium Nitrate and fuel oil mixture is the primary explosive used in the mining industry because it is inexpensive, easy to manufacture and can be easily manufactured near the mine site thus reducing the risks and expenses related to the transportation of explosives. Nitrates, Nitrites and Azides (all nitrogen compounds are either oxidizers or reactives and will react violently under the right conditions.

The triple bond in molecular nitrogen (N2) is one of the strongest in nature. The resulting difficulty of converting (N2) into other compounds, and the ease (and associated high energy release) of converting nitrogen compounds into elemental N2, have dominated the role of nitrogen in both nature and human economic activities.

Rapid release of nitrogen gas into an enclosed space can displace oxygen, and therefore represents an asphyxiation hazard. Nitrogen also dissolves in the bloodstream, and rapid decompression (particularly in the case of divers ascending too quickly) can lead to a potentially fatal condition called decompression sickness, when nitrogen bubbles form in the bloodstream. It can also cause nitrogen narcosis.

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