Chemistry, history bronze

As early as 1969, Pedersen was intrigued by the intense blue colour observed upon dissolution of small quantities of sodium or potassium metal in coordinating organic solvents in the presence of crown ethers. Indeed, the history of alkali metal (as opposed to metal cation) solution chemistry may be traced back to an 1808 entry in the notebook of Sir Humphry Davy, concerning the blue or bronze colour of potassium-liquid ammonia solutions. This blue colour is attributed to the presence of a solvated form of free electrons. It is also observed upon dissolution of sodium metal in liquid ammonia, and is a useful reagent for dissolving metal reductions , such as the selective reduction of arenes to 1,4-dienes (Birch reduction). Alkali metal solutions in the presence of crown ethers and cryptands in etheric solvents are now used extensively in this context. The full characterisation of these intriguing materials had to wait until 1983, however, when the first X-ray crystal structure of an electride salt (a cation with an electron as the counter anion) was obtained by James L. Dye and... 

The biblical Old Testament period overlaps with the Copper, Bronze, and Iron Ages, so it is natural that these metals are mentioned frequently in the Bible and in other ancient manuscripts. For example, iron is mentioned about 100 times in the Old Testament, copper 8 times, and bronze more than 150 times. Other metals that were easily obtained (tin and lead) are also described numerous times. In fact, production of metals has been a significant factor in technology and chemistry for many centuries. Processes that are crude by modem standards were used many centuries ago to produce the desired metals and other materials, but the source of raw materials was the same then as it is now. In this chapter, we will present an overview of inorganic chemistry to show its importance in history and to relate it to modern industry. 

There is no doubt that our material standard of living has risen dramatically over the last century. Much of this improvement is either the direct result of, or would be impossible without, synthetic organic chemistry. For example, modern drugs to combat a disease, electronic equipment such as telephones and computers, credit cards, cars, sports equipment, non-iron shirts, the list is endless, are all possible only because of synthetic organic chemistry. Our desire to improve our material well being has been a part of human life since it first started (we date periods of history by the technology and materials in use, hence terms such as stone age, bronze age, iron age) and is unlikely ever to cease. We will always seek to improve yet further on the materials available to us in order to provide complementary improvements in our standard of life. When I was a student, one computer would occupy a... 

Berthelot obtained ethyl peroxide from ether and ozone.He investigated photochemical reactions. His work on galvanic cells, partition coefficient, reaction velocity and equilibrium, and thermochemistry, is mentioned elsewhere. He analysed ancient metallic and other objects from Egypt and Mesopotamia, showing that the earliest so-called bronzes were pure copper, that an ancient Sumerian vase was of pure silver, and a box from Egypt was in part platinum-iridium. This work laid the foundations of chemical archaeology. His fundamental work on the history of chemistry is dealt with in Vol. I. One of his most important early researches, on glycerine, has been left over for consideration and will now be taken up. 

IN CHAPTER 22 we examined the chemistry of non-metallic elements. In this chapter we turn our attention to metals. Metals have played a major role in the development of civilization. Early history is often divided into the Stone Age, the Bronze Age, and the... 

The chemical redox potentials determined the order of the chemical advances that shaped history. On any replicate Earth, gold and silver should be the currencies of trade, the Bronze Age should come before the Iron Age, and magnesium and aluminum should not be found by the early empires. Chemistry determines the order in which metals will be discovered and used. 

Human development is clearly linked to continuous improvements in the materials used every day. Entire stages of history have been named after the critical materials—Stone Age, Bronze Age, Iron Age, and now, the Age of Plastics. When asked his opinion on chemistry s largest contribution to science and society, Lord Todd, the President of the Royal Society of London, responded I am inclined to think that the development of polymerization is, perhaps, the biggest thing chemistry has done, where it has had the biggest effect on everyday life. The world would be a totally different place without artificial fibers, plastics, elastomers, etc. (1). ... 

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