PTL:Sulfur

From ChemEd Collaborative

S is a nonmetal in the 3rd period of Group VIA. Other members of the group are oxygen (O), selenium (Se), tellurium (Te), and polonium (Po).

Contents 1 Name 2 Characteristics 3 Found 4 Uses 5 Emission Spectra

Name

The name is derived from the Sanskrit word, sulvere, and the Latin word, sulphurium. The symbol S is an abbreviation for the name. Since elemental sulfur occurs naturally, it has been known from ancient times and is referred to as brimstone in the book of Genesis in the Bible.

Characteristics

Sulfur is a pale yellow, odorless, brittle solid, which is insoluble in water but soluble in carbon disulfide. In every state, whether gas, liquid, or solid, elemental sulfur occurs in more than one allotropic form or modification. Amorphous or plastic sulfur is obtained by fast cooling of the crystalline form. Recent x-ray studies indicate that amorphous sulfur may have a helical structure with eight atoms per spiral. Crystalline sulfur seems to be made of rings, each containing eight sulfur atoms. A finely divided form of sulfur, known as flowers of sulfur, is obtained by sublimation.

Sulfur is roughly as abundant in the earth's crust as carbon.

Found

Sulfur occurs in the elemental form in nature in volcanoes and hot springs. Widely distributed in nature as sulfides:

• iron pyrites FeS₂
• galena PbS
• sphalerite ZnS (Zinc Blende)
• cinnabar HgS
• stibnite Sb₂S₃

and sulfates:

• Gypsum CaSO₄ 2H₂O
• epsom salts MgSO₄ 7 H₂O
• celestite SrSO₄
• barite BaSO₄

Minerals Containing Sulfur

Iron Pyrite	Galena	Sphalerite	Cinnabar
Stibnite	Gypsum	Celestite	Barite
Epsom Salt

Sulfur is also found in meteorites, and a dark area near the crater Aristarchus on the moon is believed to be a sulfur deposit. Sulfur readily forms sulfides with many elements, and many occur in nature as noted above.

Sulfur is commercially recovered from wells sunk into the salt domes along the Gulf Coast of the U.S. It is obtained from these wells by the Frasch process. Heated water is forced into the wells to melt the sulfur, which is then brought to the surface. Sulfur also occurs in natural gas and [petroleum] crudes and must be removed from these products. Formerly this was done chemically, which wasted the sulfur. New processes now permit recovery, and these sources promise to be very important. Large amounts of sulfur are being recovered from Alberta gas fields.

Uses

Sulfur is a component of black [gunpowder], is used in the vulcanization of natural rubber, and is used as a fungicide.

A tremendous tonnage is used to produce sulfuric acid, the most important manufactured chemical (in the U.S. and in most other countries as well). Companies produced 86.62 billion pounds of sulfuric acid in 1991. One of the first steps in the contact process to make sulfuric acid is the combustion of sulfur in air to give sulfur dioxide.

S(s) + O₂(g) SO₂(g)

It is also used in making sulfite paper and other papers, is used as a fumigant, and in the bleaching of dried fruits. The element is a good electrical insulator. Organic compounds containing sulfur are also important. These include sulfa drugs, pesticides, and compounds used in permanent wave solutions.

Emission Spectra

This is the emission spectra for Sulfur.