Production and uses of the elements

The ready reduction of Sn02 by glowing coals accounts for the knowledge of Sn and its alloys in the ancient world. Modem technology uses a reverberatory furnace at 1200-1300°. The main chemical problem in reducing Sn02 comes 

Lead is normally obtained from PbS. This is first concentrated from low-grade ores by froth flotation then roasted in a limited supply of air 

The main alloys of tin together with an indication of the percentage of total Sn production for these alloys in the USA (1991) are  

Solder (37%) (Sn/Pb) typically containing 33% Sn by weight but varying between 2-63% depending on use sometimes Cd, Ga, In or Bi are added for increased fusibility. 

Bronze (7%) (Cu/Sn) typically 5-10% Sn often with added P or Zn to aid casting and impart superior elasticity and strain resistance. Gun metal is 85% Cu, 5% Sn, 5% Zn and 5% Pb. Coinage metal and brass also often contain small amounts of Sn. World production of bronzes approaches SOO 000 tonnes pa. 

Bronze (7%) ( 2u/Sn) typically S-10% Sn often with added P or Zn to aid casting and impart superior 

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This review describes factors concerning the safety and environmental effects of organic germanium, tin and lead compounds. The factors involve the production and use of the elements, alkylation, degradation, toxicity, health effect assessment and so on. 

Inorganic chemistry draws its strength from its great practical utility, and this book presents the subject from the standpoint of applications rather than the customary one of quantum mechanical bonding theory. Since the quintessential subject matter is the properties of the 112 known chemical elements and their compounds, we begin with a consideration of the availability of the commonest elements in the Earth s crust (Table 1.1), hydrosphere (i.e., oceans, lakes, rivers, snowfields, ice caps, and glaciers), and atmosphere, along with brief summary of the production and uses of these elements and their compounds. 

It is readily apparent that oxygen and its compounds are used in quantities that are almost beyond comprehension. Sulfuric acid is by far the leading chemical in terms of production. This compound is used in numerous manufacturing processes both in heavy industry and in specialty preparations and consists of over 65% oxygen. Sulfuric acid is so widely used that it has been stated that the production and use of the chemical provides a barometer for gauging the status of the economy. In the sections that follow, we will explore some of the chemistry of this most important element, oxygen. 

Be made from elements available in most locations to reduce the amount of shipping required in the production and use of the fuel. 

Special problems are, of course, created by the general use of particularly toxic elements, such as antimony, arsenic, beryllium, cadmium, lead, mercury and thallium, in our society. The production and use of these elements and their compounds is inevitably associated with some release into the environment and there are public health problems in factories and laboratories arising at the initial stage of dispersion. Such problems may be regarded as primary problems of environmental pollution. They are often acute since they may involve direct exposure to a highly toxic element, or one of its compounds, before it has been substantially diluted in the environment. For example. 

Production and Uses of Silicon Elemental silicon is produced when quartz or sand (Si02) is reduced by reaction with coke in an electric arc furnace. The balanced chemical equation for the reaction is given below ... 

Mangrove ecosystems are an example of one of the most productive ecosystems of the World. The biomass pool is in excess of 100 ton/ha of dry matter and annual NPP varies from 10 to 30 ton/ha, including leaf litter production of 8-15 ton/ha. Using average data on annual net primary production and content of various elements, we... 

No one person is given credit for the discovery or identification of irons minerals/ores or the technologies involved in the sophisticated metallurgical processes used today. Many people have contributed to the understanding of the chemistry and how to make practical use of this important element. Modern civilization, with its many skyscrapers, large ships, trains, cars, and so forth, would not be possible without the knowledge and uses of the many iron and steel products manufactured today. 

Chlorine is by far the most useful of the elements of the halogen family. This fact becomes evident when one learns that the annual production of chlorine in the United States alone amounts to approximately 250,000 tons. Much of this chlorine is used in the bleaching of fabrics, wood pulp, and so forth. Considerable quantities of this element are used in treating water supplies for the purpose of destroying harmful bacteria. Many of the poisonous gases used in the world wars were chlorine compounds, such as mustard gas [(C1C2H4)2S], chloropicrin... 

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