Chalcogen

(Redirected from Oxygen family)
Jump to: navigation, search
Group 16
Period
2 8
O
3 16
S
4 34
Se
5 52
Te
6 84
Po
7 116
Uuh


Overview

The chalcogens (with the "ch" pronounced like a k) are the name for the periodic table group 16 (old-style: VIB or VIA) in the periodic table. It is sometimes known as the oxygen family. It consists of the elements oxygen (O), sulfur (S), selenium (Se), tellurium (Te), the radioactive polonium (Po), and the synthetic ununhexium (Uuh). The compounds of the heavier chalcogens (particularly the sulfides, selenides, and tellurides) are collectively known as chalcogenides. Unless grouped with a heavier chalcogen, oxides are not considered chalcogenides.

The name is generally considered to mean "ore former" from the Greek chalcos "ore" and -gen "formation". [1]

Oxygen and sulfur are nonmetals, and polonium, selenium and tellurium are metalloid semiconductors (i.e., their electrical properties are between those of a metal and an insulator). Nevertheless, tellurium, as well as selenium, is often referred to as a metal when in elemental form.

Chalcogens are quite common as minerals. For example, pyrite (FeS2) is an iron ore and AuTe2 gave its name to the gold rush town of Telluride, Colorado in the United States.

The formal oxidation number of the chalcogen is generally -2 in a chalcogenide but other values, such as -1 in pyrite, can be attained.

The highest formal oxidation number +6 is found in sulfates, selenates and tellurates, such as in sodium selenate (Na2SeO4). Modern chemical understanding based on quantum theory somewhat outdates the use of formal oxidation numbers in favour of a many-electron wavefunction approach allowing detailed computer simulation, though the concept, while flawed, is still useful in thought experiments.

Explanation of above periodic table slice:
Nonmetals Metalloids Poor metals Atomic numbers in red are gases Atomic numbers in black are solids Solid borders indicate primordial elements (older than the Earth) Dashed borders indicate radioactive natural elements Dotted borders indicate radioactive synthetic elements

WikiDoc Resources for Chalcogen

Articles

Most recent articles on Chalcogen

Most cited articles on Chalcogen

Review articles on Chalcogen

Articles on Chalcogen in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Chalcogen

Images of Chalcogen

Photos of Chalcogen

Podcasts & MP3s on Chalcogen

Videos on Chalcogen

Evidence Based Medicine

Cochrane Collaboration on Chalcogen

Bandolier on Chalcogen

TRIP on Chalcogen

Clinical Trials

Ongoing Trials on Chalcogen at Clinical Trials.gov

Trial results on Chalcogen

Clinical Trials on Chalcogen at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Chalcogen

NICE Guidance on Chalcogen

NHS PRODIGY Guidance

FDA on Chalcogen

CDC on Chalcogen

Books

Books on Chalcogen

News

Chalcogen in the news

Be alerted to news on Chalcogen

News trends on Chalcogen

Commentary

Blogs on Chalcogen

Definitions

Definitions of Chalcogen

Patient Resources / Community

Patient resources on Chalcogen

Discussion groups on Chalcogen

Patient Handouts on Chalcogen

Directions to Hospitals Treating Chalcogen

Risk calculators and risk factors for Chalcogen

Healthcare Provider Resources

Symptoms of Chalcogen

Causes & Risk Factors for Chalcogen

Diagnostic studies for Chalcogen

Treatment of Chalcogen

Continuing Medical Education (CME)

CME Programs on Chalcogen

International

Chalcogen en Espanol

Chalcogen en Francais

Business

Chalcogen in the Marketplace

Patents on Chalcogen

Experimental / Informatics

List of terms related to Chalcogen

See also

External links




Linked-in.jpg