Sulfur

Sulfur (or sulphur; see spelling below) is the chemical element in the periodic table that has the symbol S and atomic number 16. It is an abundant, tasteless, odorless, multivalent non-metal. Sulfur, in its native form, is a yellow crystaline solid. In nature, it can be found as the pure element or as sulfide and sulfate minerals. It is an essential element for life and is found in several amino acids. Its commercial uses are primarily in fertilizers but it is also widely used in gunpowder, matches, insecticides and fungicides.

Compounds

Hydrogen sulfide has the characteristic smell of rotten eggs. Dissolved in water, hydrogen sulfide is acidic and will react with metals to form a series of metal sulfides. Natural metal sulfides are common, especially those of iron. Iron sulfide is called pyrite, the so called fool's gold. Interestingly, pyrite can show semiconductor properties.http://home.earthlink.net/~lenyr/iposc.htm Galena, a naturally occurring lead sulfide, was the first semiconductor discovered, and found a use as a signal rectifier in the "cat's whiskers" of early crystal radios.

Related Topics:
Hydrogen sulfide - Pyrite - Galena - Semiconductor - Rectifier - Crystal radio

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Many of the unpleasant odors of organic matter are based on sulfur-containing compounds such as ethyl and methyl mercaptan used to scent natural gas so that leaks are easily detectable. The odor of garlic and "skunk stink" are also caused by sulfur containing organic compounds. However, not all organic sulfur compounds smell unplesant, margin, a sulfur containing terpene is responsible for the characteristic scent of grapefruit.

Related Topics:
Mercaptan - Garlic - Skunk - Terpene - Grapefruit

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Polymeric sulfur nitride has metallic properties even though it does not contain any metal atoms. This compound also has unusual electrical and optical properties. This polymer can be made from tetrasulfur tetranitride S4N4.

Related Topics:
Metal - Tetrasulfur tetranitride

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Other important compounds of sulfur include:

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INORGANIC:

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• Sulfides (S^2-) are simple compounds of sulfur with some other chemical element.
• Sulfites (SO₃^2-), the salts of sulfurous acid, H₂SO₃, created by dissolving SO₂ in water. Sulfurous acid and the corresponding sulfites are fairly strong reducing agents. Other compounds derived from SO₂ include the pyrosulfite or metabisulfite ion (S₂O₅²⁻).
• Sulfates (SO₄^2-), the salts of sulfuric acid. Related to this, sulfuric acid also reacts with SO₃ in equimolar ratios to form pyrosulfuric acid (H₂S₂O₇).
• Thiosulfates (sometimes refered as thiosulfites or "hyposulfites") (S₂O₃²⁻). Thiosulfates are used in photographic fixing (HYPO)as reducing agents and ammonium thiosulfate is being investigated as a cyanide replacement in leaching gold.http://doccopper.tripod.com/gold/AltLixiv.html
• Sodium dithionite, Na₂S₂O₄ from hyposulfurous/dithionous acid, a powerful reducing agent.
• Sodium dithionate (Na₂S₂O₆)
• Polythionic acids (H₂S_nO₆), where n can range from 3 to 80.
• Peroxymonosulfuric acid (H₂SO₅) and peroxydisulfuric acids (H₂S₂O₈), made from the action of SO₃ on concentrated H₂O₂, and H₂SO₄ on concentrated H₂O₂ respectively.
• Sodium polisulfides (Na₂S_x)
• Sulfur hexafluoride, SF₆, a heavy, gaseous, non-reactive and non-toxic propellant
• Tetrasulfur tetranitride S₄N₄.
• Thiocyanates are compounds containing the thiocyanate ion, SCN^-. Related to this there is thiocyanogen, (SCN)₂.

ORGANIC:

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• dimethylsulfoniopropionate (DMSP; (CH₃ )₂S⁺CH₂CH₂COO^-) which is the central component of the marine organic sulfur cycle.
• A thioether is a molecule with the form R-S-R′, where R and R′ are organic groups. These are the sulfur equivalents of ethers.
• A thiol (also known as a mercaptan) is a molecule with an -SH functional group. These are the sulfur equivalents of alcohols.
• A thiolate ion has an -S^- functional group attached. These are the sulfur equivalent of alkoxide ions.
• A sulfoxide is a molecule with an R-S(=O)-R′ functional group where R and R′ are organic groups. A common example of a sulfoxide is DMSO.
• A sulfone is a molecule with an R-S(=O)-R′ functional group where R and R′ are organic groups.
• Lawesson's reagent is a chemical reagent which can remove oxygen from other organic molecules and replace it with sulfur.
• Napthalen-1,8-diyl 1,3,2,4-dithiadiphosphetane 2,4-disulfide