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Elements, ancient

Sulfur was known in the days of early humans. No single person can take credit for its discovery. It was probably one of the first free elements ancient humans tried to use and understand besides the always known air, fire, and water. [Pg.235]

Greek ideas of an element Ancient Greeks worried about the nature of elements for centuries. Finally, they came to the conclusion that Fire, Earth, Air and Water were the four elements and everything was made up of these elements in different proportions. [Pg.175]

Group 5A Elements (Ancients, Magnus, Brandt, Geoffrey, D. Rutherford)... [Pg.590]

Group 6A Elements (Ancients, Priestley, Muller, Berzelius, the Curies)... [Pg.590]

Roofs are a basic element of shelter from inclement weather. Natural or hewn caves, including those of snow or ice, ate early evidence of human endeavors for protection from the cold, wind, rain, and sun. Nomadic people, before the benefits of agriculture had been discovered and housing schemes developed, depended on the availabiUty of natural materials to constmct shelters. Portable shelters, eg, tents, probably appeared early in history. Later, more permanent stmctures were developed from stone and brick. SaUent features depended strongly on the avadabihty of natural materials. The Babylonians used mud to form bricks and tiles that could be bonded with mortars or natural bitumen. Ancient buildings in Egypt were characterized by massive walls of stone and closely spaced columns that carried stone lintels to support a flat roof, often made of stone slabs. [Pg.209]

Introduction The enchanting flame has held a special mystery and charm the world over for thousands of years. According to Greek myth, Prometheus the Titan stole fire from the heavens and gave it to mortals—an act for which he was swiftly punished. Early people made use of it anyway. Soon the ancients came to regard fire as one of the basic elements of the world. It has since become the famihar sign of the hearth and the mark of youth and blood—as well as the object of intense curiosity and scientific investigation. [Pg.2313]

The alkali metals form a homogeneous group of extremely reactive elements which illustrate well the similarities and trends to be expected from the periodic classification, as discussed in Chapter 2. Their physical and chemical properties are readily interpreted in terms of their simple electronic configuration, ns, and for this reason they have been extensively studied by the full range of experimental and theoretical techniques. Compounds of sodium and potassium have been known from ancient times and both elements are essential for animal life. They are also major items of trade, commerce and chemical industry. Lithium was first recognized as a separate element at the beginning of the nineteenth eentury but did not assume major industrial importance until about 40 y ago. Rubidium and caesium are of considerable academic interest but so far have few industrial applications. Francium, the elusive element 87, has only fleeting existence in nature due to its very short radioactive half-life, and this delayed its discovery until 1939. [Pg.68]

Sodium, 22 700 ppm (2.27%) is the seventh most abundant element in crustal rocks and the fifth most abundant metal, after Al, Fe, Ca and Mg. Potassium (18 400 ppm) is the next most abundant element after sodium. Vast deposits of both Na and K salts occur in relatively pure form on all continents as a result of evaporation of ancient seas, and this process still continues today in the Great Salt Lake (Utah), the Dead Sea and elsewhere. Sodium occurs as rock-salt (NaCl) and as the carbonate (trona), nitrate (saltpetre), sulfate (mirabilite), borate (borax, kemite), etc. Potassium occurs principally as the simple chloride (sylvite), as the double chloride KCl.MgCl2.6H2O (camallite) and the anhydrous sulfate K2Mg2(S04)3 (langbeinite). There are also unlimited supplies of NaCl in natural brines and oceanic waters ( 30kgm ). Thus, it has been calculated that rock-salt equivalent to the NaCl in the oceans of the world would occupy... [Pg.69]

The use of thermal insulation dates back to ancient times, when primitive man used animal skins for clothing and built structures for protection from the elements. Primitive insulation included fibrous materials such as animal fur or wool, feathers, straw, or woven goods. Bricks and stone, while not highl y efficient thermal insulation, provided protection from the elements, reduced the loss of heat from fires, and provided large masses that moderate temperature changes and store heat. [Pg.674]

In chemistry, an element is identified by its symbol. This consists of one or two letters, usually derived from the name of the element. Thus the symbol for carbon is C that for aluminum is Al. Sometimes the symbol comes from the Latin name of the element or one of its compounds. The two elements copper and mercury, which were known in ancient times, have the symbols Cu (cuprum) and Hg (hydrargyrum). [Pg.3]

Just like chemists today, ancient Egyptians also used symbols as well as words to represent common elements and compounds. Electrum is an alloy of silver and gold. [Pg.25]

Each element has been named and, for convenience, has been given a nickname—a shorthand symbol of one or two letters. Thus the element carbon is symbolized by the letter C, the element neon by the letters Ne. The symbols are adopted by international agreement among chemists. Eleven of the elements have names derived from the capitalized first letter of the Latin name of the element and, if necessary, by a second letter (uncapitalized). These eleven include seven common metals known to the ancients. (See Table 2-V.)... [Pg.30]

Many of the metals used by ancient man— coppei (cuprum, Cu), silver (argentum, Ag), gold (aurum, Au), tin (stannum, Sn), and lead (plumbum, Pb)—are in relatively short supply. Ancient man found deposits of the first three occurring as the elementary metals. These three may also be separated from their ores by relatively simple chemical processes. On the othei hand, aluminum and titanium, though abundant, are much more difficult to prepare from their ores. Fluorine is more abundant in the earth than chlorine but chlorine and its compounds are much more common—they are easier to prepare and easier to handle. However, as the best sources of the elements now common to us become depleted, we will have to turn to the elements that are now little used. [Pg.441]

The ancient Greeks had much the same idea. They supposed that there were four elements—earth, air, fire, and water—that could produce all other substances when combined in the right proportions. Their concept of an element is similar to our own but, on the basis of experiments, we now know that there are actually more than 100 elements, which—in various combinations—make up all the matter on earth (Fig. B.l). [Pg.39]

Arsenic and antimony are metalloids. They have been known in the pure state since ancient times because they are easily obtained from their ores (Fig. 15.3). In the elemental state, they are used primarily in the semiconductor industry and in the lead alloys used as electrodes in storage batteries. Gallium arsenide is used in lasers, including the lasers used in CD players. Metallic bismuth, with its large, weakly bonded atoms, has a low melting point and is used in alloys that serve as fire detectors in sprinkler systems the alloy melts when a fire breaks out nearby, and the sprinkler system is activated. Like ice, solid bismuth is less dense than the liquid. As a result, molten bismuth does not shrink when it solidifies in molds, and so it is used to make low-temperature castings. [Pg.745]

White, C.D. and Schwarcz, H.P. 1989 Ancient Maya diet as inferred from isotopic and elemental analysis of human bone. JoumaZ o/ Archaeological Science 16 451M74. [Pg.37]

Weydert, J. 1990 Elemental Analysis of Bone for Ancient Diet Reconstruction. Unpublished Ph.D. dissertation. Northwestern University. [Pg.171]

The element phosphorus, like nitrogen, is essential to plant and animal life. Although phosphorus was not identified and isolated until 1669, phosphorus-containing materials have been used as fertilizers since ancient times, usually from bird droppings, fish, and bone. The first phosphoric acid was made by treating bone ashes with sulfuric acid. This marked the beginning of the commercial fertilizer industry. Eventually, mined phosphate rock, a poor fertilizer by itself, was substituted for bones as a raw material for phosphoric acid in the mid-1880s. [Pg.25]

To these ancient identities was added in due course the historical Jesus.It was the apostle Paul who established the dehnitive Christian dogma concerning the nature of Christ. His account recalls the role of the ancient Iranian and Jewish Saviour figure (although the exact relationship to the pagan elements is the subject of serious contention on the part of Christian theology). [Pg.26]

The elements listed in Table TJ have symbols derived from their names in other languages. Most of these elements were known in ancient times, so their symbols reflect the Latin language that was dominant when they were named. [Pg.14]

Fertilization using animal products has been practiced since ancient times. Animal manure returns nutrients to the soil, replenishing elements that are depleted as crops are grown and harvested. It is likely that the use of animal fertilizers quickly followed the domestication of goats, sheep, and cattle. [Pg.215]

In the epic poem, Rime of the Ancient Mariner, a becalmed sailor laments Water, water, everywhere, nor any drop to drink. With regard to the element nitrogen, we might say N2,N2, everywhere, nor any N to eat. Even though the atmosphere of our planet is 80% molecular nitrogen, plants are unable to break the extremely strong NON triple bond. Instead, plants must rely on other sources for the nitrogen atoms that are essential for the synthesis of biomolecules such as amino acids and DNA. [Pg.1016]

Six elements are metalloids B, Si, Ge, As, Sb, and Te. Of these, silicon is by far the most abundant, making up over 27% of the Earth s crust, more than any other element except oxygen, hi fact, S1O2 and silicate minerals account for 80% of the atoms near the Earth s surface. Despite its great abundance, silicon was not discovered until 1824, probably because the strong bonds it forms with oxygen makes silicon difficult to isolate. Two much rarer metalloids, antimony (known to the ancients) and arsenic (discovered ca. 1250 ad) were isolated and identified long before silicon. [Pg.1521]


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See also in sourсe #XX -- [ Pg.72 ]




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Elements ancient Greece

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Elements known to the ancient world

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