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Gaffer Variety:
Elements 12 SN2 014:
By Willie Gaffer:
Sulfur:
Sulfur, symbol S, is a pale yellow nonmetallic element occurring widely in nature in several free and combined allotropic forms. It is used in black gunpowder, rubber vulcanization, the manufacture of insecticides and pharmaceuticals, and in the preparation of sulfur compounds such as hydrogen sulfide and sulfuric acid. The atomic number is 16, the atomic weight is 32.064 and the melting point is 112.8°C in the rhombic form. In the monoclinic form, it is 119.0°C. The boiling point is 444.6°C, the specific gravity 2.07 in the rhombic form, and1.957 in the monoclinic form. The electron shell configuration is 2, 8, and 6 and the valences are 2, 4, and 6. It occupies group 6A of the periodic table.
Sulfur in its natural form is a tasteless, odorless, light yellow solid. Compounds of sulfur occur in dairy products and eggs. They are an essential dietary ingredient. However, hydrogen sulfide (H2S), is quite poisonous. Fortunately, although it is very similar to water (H2O), it smells like rotting eggs so no one is likely to drink it. Sulfur burns with a pale blue flame and produces sulfur dioxide (SO2), which when further oxidized and combined with atmospheric moisture, is one of the principal ingredients of acid rain.
In the not so good olden days sulfur was called brimstone. It was isolated in 1777 by Lavoisier. This is the French chemist who is also the founder of modern chemistry. He isolated the major components of air disproved the phlogiston theory by determining the role of oxygen in combustion, and organized the classification of compounds. Of course, he was a scientist so he was executed during the Reign of Terror.
Sulfur is the ninth most abundant element in the universe.
In the form of sulfides, sulfates, and elemental sulfur, it makes up about 0.03
percent of the Earth's crust. After oxygen and silicon, it is the most abundant
mineral. Free sulfur occurs chiefly in volcanic or sedimentary deposits. The
former are located throughout the world. The sedimentary deposits are most
common along the
Sulfur-containing ores include such sulfides as pyrite (iron disulfide), galena (lead sulfide), cinnabar (mercury sulfide), sphalerite (zinc sulfide), and chalcopyrite (copper iron sulfide), as well as such sulfates as gypsum (calcium sulfate) and barite or heavy spar (barium sulfate).
Sulfur is one of the four most important basic chemical
commodities. When it is recovered and process from
salt domes along the gulf it produces a very pure form. In this process, wells
are drilled into the sulfur formation and then lined with a large pipe in which
an air pipe and a water pipe of smaller diameter are placed.
Superheated water, injected into the circular space between the pipes
penetrates the cap rock through holes on the bottom of the pipe. As the sulfur
melts, it settles to the bottom of the deposit. From there it is pumped to the surface by applying air pressure through
the central pipe. Several such wells operate under the ocean floor in the
Sulfuric acid is one of the most valuable of all chemicals. Prepared commercially by the reaction of water with sulfur trioxide, the compound is used in manufacturing fertilizers, pigments, dyes, drugs, explosives, detergents, and inorganic salts and esters. Sulfurous acid, H2SO3, is made by adding sulfur dioxide to water. Its most important salt is sodium sulfite, Na2SO3. This is a reducing agent used in the manufacture of paper pulp, photography, and in the removal of oxygen from boiler feedwater.
The organic compounds of sulfur constitute a diverse and important subdivision of organic substances. Some examples include the sulfur-containing amino acids (e.g., cysteine, methionine, and taurine), which are key components of hormones, enzymes, and coenzymes. Significant, too, are the synthetic organic sulfur compounds, among them numerous pharmaceuticals (sulfa drugs, dermatological agents), insecticides, solvents, and agents such as those used in preparing rubber and rayon.
Chlorine:
Chlorine, symbol Cl, is a highly irritating, greenish-yellow gaseous halogen, capable of combining with nearly all other elements. It is produced by electrolysis of sodium chloride. It is used to purify water, as a disinfectant, a bleaching agent, and in the manufacture of many important compounds including chloroform and carbon tetrachloride. The atomic number is 17, the atomic weight is 35.45, the freezing point is -100.98°C, the boiling point is -34.6°C, and the specific gravity is 1.56 (-33.6°C). The electron shell configuration is 2, 8, and 7. The valences of chlorine are 1, 3, 5 and 7. It lives in group 7A of the periodic table.
Chlorine is toxic. It will play real heck with the respiratory system and the eyes of all animals including us. It was used as a poison gas in WWI with devistating results, sometimes on the perpetrators as the winds shifted. Good show! It is two and a half times heavier than air It was first made from a mixture of hydrochloric acid and manganese dioxide in 1774 by Carl Wilhelm Scheele. In 1810 Sir Humphry Davy showed that it cannot be decomposed proving that it is an element. He named it chlorine.
Chlorine is the 20th most abundant element in the
earth making up about 0.013 percent of the crust. Free chlorine has been reported as a minor constituent of volcanic gases,
of which hydrogen chloride is a common component. Chlorine, as the chloride ion
Cl-, is the main negative ion in ocean water, being
1.9 percent by weight. It is also found in inland seas
such as the
Most chlorine is industrially produced by the electrolysis of brine. This is how it is done in the chemical producing companies of South East Michigan. Hot water is pumped down into the salt domes below the surface to dissolve the salt. The resultant brine is then pumped out of the shaft and processed. Some is also obtained as a by-product in the manufacture of sodium metal by the electrolysis of molten sodium chloride. Chlorine and its compounds are used extensively for bleaching in the paper and textile industries, for disinfecting municipal water supplies, for household bleaches and germicides, and for the production of many organic and inorganic chemicals.
Chlorine molecules are composed of two atoms (Cl2). It readily combines with almost all the elements. Some exceptions are oxygen, fluorine, nitrogen, carbon, and the noble gases. Chlorine enters directly or as an intermediate into the synthesis of many organic chemicals that are used as solvents, dyes, plastics, and synthetic rubber.