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Making Elements Elemental

Some of the first steps toward understanding how the basic corpuscles of matter behaved came from what might seem like an unlike source meteorology. John Dalton (1766-1844), bom in Manchester, began to study weather in 1787. He also studied Newton s Principia and as a result was conversant with the concept of the inverse square law. Newton had used it to show that the attraction of gravity decreased as the square of the distance between objects. This mathematical relationship also applied to a range of other physical phenomena, such as luminosity. When considering questions about precipitation— why there was fog, rain, and snow—he discovered that the quantity of water vapor in a gas was independent of the type of gas but dependent on the temperature of the gas. [Pg.67]

This led him to question the idea that the atmosphere was a chemical compound. Instead, he began to think of it as a mixture of different gases that existed independently. To understand the distinction, consider a cup of hot chocolate. The cup seems to contain a uniform substance that is made by [Pg.67]

In 1801, Dalton formulated the law of partial pressure. He argued that the pressure exerted by one type of gas in a mixture was independent of the pressure exerted by another type of gas. In a fixed volume, the observed pressure was then the total pressure made up of the sum of pressures exerted by each gas. [Pg.68]

With these ideas as a foundation for understanding matter, Dalton went on to publish his New System of Chemical Philosophy (vol. 1, part 1,1808, part 2, 1810 vol. 2, 1827). In it, Dalton presented his new theory of atomism. Dalton made four assumptions about atoms and the compounds built up from these ultimate particles. [Pg.68]

he started with the idea that the simple particles were indestructible and that they remained unchanged even when in combination with other things. Although this was not easily proven as universally true in Dalton s [Pg.68]


Economic Aspects and Uses. Magnesium hydroxide and magnesium chloride are used as a basic feedstock to make elemental magnesium, MgO refractories, and reactive chemicals. One hundred and sixty thousand tons of magnesium metal were produced ia the United States in 1989 in addition to 1,013,000 tons of MgO equivalent in magnesium compounds (qv) (54). [Pg.412]

Magnesium is removed from brines of the Great Salt Lake in the form of magnesium chloride. This is then used to make elemental magnesium, dust suppressants, and bischofite flake. Magnesium chloride is also used in drilling mud, ion-exchange resins, oxi-chloral cements, fertilizers, and miscellaneous industrial uses. [Pg.412]

C04-0145. Silicon tetrachloride is used in the electronics industry to make elemental silicon for computer chips. Silicon tetrachloride is prepared from silicon dioxide, carbon graphite, and chlorine gas. [Pg.276]

The most efficient way to make elements 93 and 94 uses neutrons produced during fission in nuclear reactors... [Pg.1577]

The solution is regenerated by heat to provide a sulfur-rich gas which can be used to make elemental sulfur, sulfuric acid, or sulfur dioxide. A small amount of sodium sulfate is produced, which must be crystallized out and disposed of. Initially the process used the potassium salts. Developed in the late 1960s. Licensed by Davy McKee and used in 22 plants in the United States, Japan, Germany, and Austria. [Pg.290]

The sixth element in the periodic table, carbon, has the electron configuration 2s 2 and, thus, has 4 valence electrons in the unfilled orbitals of its second electron shell. To fill these orbitals to a stable set of 8 valence electrons, a single carbon atom may share electrons with 2, 3, or even 4 other atoms. No other element forms such strong bonds to as many other atoms as carbon does. Moreover, multiple carbon atoms readily link together with single, double, or triple bonds. These factors make element number 6 unique in the entire periodic table. The number of carbon-based compounds is many times greater than the total of all compounds lacking carbon. [Pg.58]

Most of the world production of phosphates goes into fertilizer, but some is used as detergent builders (Section 7.7). In toothpastes, calcium pyrophosphate has proved effective as a mild abrasive in eliminating tartar, while Na2[FP03], made by reaction of NaF with cyclic sodium metaphosphates (NaP03), is widely used as a fluoridating agent to suppress dental caries (Section 12.3). A minor amount of rock phosphate is used to make elemental phosphorus by reduction with coke in the presence of silica in the electric furnace (see Section 17.7) ... [Pg.186]

To make elements artificially, we need to simulate the conditions found inside a star. To overcome the energy barriers to nuclear synthesis,... [Pg.954]

Inorganic pigments and lakes (organic dyes bonded to an inorganic support) can be recognized by the ratio of elements in their composition, making elemental analysis an important tool in their identification. EDS may facilitate an initial qualitative analysis, but quantitative analysis and the detection of trace elements are needed to identify the inorganic colorant components. Due to sample size restrictions, the methods that can be employed are limited. The techniques of inductively-coupled plasma mass spectrometry (ICP-MS), ICP-optical emission spectroscopy (ICP-OES), and laser ablation ICP-MS are described in the literature (56). [Pg.26]

A check can be made by making element balances in moles. ... [Pg.48]

Hydrocarb A hypothetical process for making methanol from biomass, which simultaneously makes elemental carbon for storage or use as a fuel. Developed in the 1990s at the Brookhaven National Laboratory, New York. See also Carnol, Hynol. [Pg.177]

Plasticized sulfur is a hot-melt adhesive and fulfills more of these requirements than any presently available, commercial glue. However, modified sulfur cannot be applied with present production equipment, and sulfur lacks many important, frequently required qualifications, among them fire resistance and resistance to heat. Thus, substantially more work would be necessary to make elemental sulfur a viable commercial bulk glue. However, we found that elemental sulfur can be polymerized in situ with formaldehyde resins (5,33), and this yields bonds which have good mechanical properties, moisture resistance, and promising high-temperature behavior. Such glues can be handled with presently available equipment and presently common process conditions (35,36). These materials are described separately (33). [Pg.276]

A similar route, bombardment of 2 Cm with Ca, was used to make element 116 (Uuli) it alpha-decayed after 47 ms to a known isotope of element 114 ... [Pg.228]

MEASUREMENT METRICS Use Metrics to Make Element Corrective Action Decisions Conduct Metrics Acquisition Maintain a Dependable Practice... [Pg.182]

Credit for discovery of a transfermium element is extremely complicated. In most cases, no more than a handful of atoms is produced in an atom smasher. For example, the Dubna group first claimed to have found element 104 in 1964, but many scientists doubted this report. Five years later, American scientists also reported making element 104. This time, the evidence was better. [Pg.629]

Molten sodium chloride is used for making elemental sodium and chlorine. Suppose the electrical power to a vat containing 56.2 kg molten sodium chloride is cut off and the salt crystallizes (without changing its temperature). Calculate the enthalpy change, using data from Table 12.2. [Pg.524]

Complete and balance the following equations for nuclear reactions that are used in particle accelerators to make elements heyond uranium ... [Pg.819]

Note that instead of making mole balances on CO2 and O2 as in Example 2.3, we could have made mole, or mass, balances on the elements C and 0 (or oxygen expressed as O2) that would lead to the same final information. You can avoid using the generation and consumption terms in Eq. (2.1) if you make element balances. [Pg.113]

And then the entire structure came under attack by a group of physicists and physical chemists who rejected the very idea of material atoms. These scientists, called the Energeticists, argued that everything was made up of fields of force. This new physics would undermine the foundation of the periodic table. It wouldn t exactly make elements disappear, but it would certainly transform them from physical objects into a collection of characteristics. [Pg.87]

Scientists around the world have been working on controlled fusion for many years. The theoretical and practical problems are considerable, but if fusion could be made to happen, one of the potential products would be the ability to custom-make elements. [Pg.110]

It s time to clean out your room—again. Where do all these things come from Some are made of cloth and some of wood. The books are made of paper and an endless array of things are made of plastic. Fewer than 100 different kinds of naturally occurring elements are found on Earth. They combine to make all these different substances. What makes elements form chemical bonds with other elements The answer is in their electrons. [Pg.7]

We had very good reason to think that molybdenum bombarded by deuterons would make element 43, which we now call technetium. Molybdenum has 42 protons in its nucleus. A deuteron, the nucleus of a deuterium or heavy hydrogen atom, has 1 proton and 1 neutron. Technetium, of course, has 43 protons in its nucleus. [Pg.121]

Domestic supplies of vanadium are obtained from a deposit in Arkansas that is mined for vanadium alone from some deposits in the western states that yield coproduct uranium and vanadium and from slags derived from making elemental phosphorus from phosphate rock mined in Idaho. The vanadium-production potential of these deposits does not appear to be adequate to satisfy long-range domestic requirements. [Pg.202]

In addition, the UMBRA initiative by CIRS incorporates many benefit-risk activities and proposed a unified benefit-risk framework with the following eight steps embedded within a core of decision-making elements (CIRS). [Pg.273]

Experiments to make elements 104 through 111 require using projectiles bigger than alpha particles or neutrons, (a) True, (b) False. [Pg.299]


See other pages where Making Elements Elemental is mentioned: [Pg.67]    [Pg.69]    [Pg.71]    [Pg.1324]    [Pg.414]    [Pg.826]    [Pg.111]    [Pg.66]    [Pg.163]    [Pg.880]    [Pg.67]    [Pg.69]    [Pg.71]    [Pg.12]    [Pg.1260]    [Pg.1324]    [Pg.662]    [Pg.654]    [Pg.687]    [Pg.856]    [Pg.235]    [Pg.332]    [Pg.263]    [Pg.707]    [Pg.68]   


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The atom factories Making new elements

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