Metals coloration

Potassium, a soft, low density, silver-colored metal, has high thermal and electrical conductivities, and very low ionization energy. One useful physical property of potassium is that it forms Hquid alloys with other alkah metals such as Na, Rb, and Cs. These alloys have very low vapor pressures and melting points. 

Va.na.dium (II) Oxide. Vanadium(II) oxide is a non stoichiometric material with a gray-black color, metallic luster, and metallic-type electrical conductivity. Metal—metal bonding increases as the oxygen content decreases, until an essentially metal phase containing dissolved oxygen is obtained (14). 

Schilf-glascrz, n. freieslebenite. -rohr, n. reed. Schiller, m. play of colors, iridescence surface color, metallic color, schiller. -farbe, /. changeable color schiller color, surface color, metallic color. 

Multicolor or single color metallics (not as good as hot stamp). 

A solid that contains cations and anions in balanced whole-number ratios is called an ionic compound. Sodium chloride, commonly known as table salt, is a simple example. Sodium chloride can form through the vigorous chemical reaction of elemental sodium and elemental chlorine. The appearance and composition of these substances are very different, as Figure 2-24 shows. Sodium is a soft, silver-colored metal that is an array of Na atoms packed closely together. Chlorine is a faintly yellow-green toxic gas made up of diatomic, neutral CI2 molecules. When these two elements react, they form colorless ciystals of NaCl that contain Na and Cl" ions in a 1 1 ratio. 

Alternatively, an aqueous solution of sodium diethyldithiocarbamate (3.5%, 2 ml) or freshly prepared solution of dithizone in chloroform (0.1%, 10 ml) was added to sample A. The metal diethyldithiocarbamates (termed sample B) or metal dithizon-ates (termed sample C) thus formed were extracted in chloroform. The volume of chloroform extract was reduced to 1.0 ml. Aliquots (10 pi) each of sample B and sample C were chromatographed on plates coated with 0.25-mm layer of silica gel G using benzene -t methyl isopropylketone (50 1) and toluene -r chloroform (50 1), respectively, as mobile phases. Metal dithizonates were self-detected. The namral colored metal diethyldithiocarbamates were converted into brown spots by spraying... 

Glass color Coloring metal Glass furnace environment... 

Limestone varieties differ greatly from one another in their texture and the impurities they contain, and consequently they also differ in color. The color of limestone may vary from white (when it contains practically no impurities) to off-white and even to intensely colored. Minor inclusions within the limestone structure are often of silica, usually in a concentration below 5%, as well as feldspar and clay in still lesser amounts. Many types of limestone also include embedded fossils. Much limestone deposits in the outer crust of the earth are altered during geologic metamorphic processes that involve mainly pressure and heat but also liquids and gases. Marble, for example, a metamorphic rock derived from calcium carbonate, is white when composed only of this substance colored metal ions and other impurities impart to marble a wide range of colors such as red, yellow, and green and also give... 

Primary clay, for example kaolin, is colorless, and when such clay is heated to a high temperature it produces white ceramic materials. Most pottery, however, is colored its color is due to the fact that most of it was, and still is, made not from primary but from secondary clay. Secondary clay contains minerals other than clay, and colored metal ions in them endow the pottery with their color. Iron ions (in iron oxides), for example, tend to make pottery yellow, brown, or red, and manganese ions (in pyrolusite, a mineral composed of manganese oxide) make it either dark or black. 

Perhaps the simplest archaeological question that can be answered by chemical means is what is this object made from . The chemical identity of many archaeological artifacts may be uncertain for a number of reasons. Simply, it may be too small, corroded, or dirty to be identified by eye. Alternatively, it may be made of a material that cannot be identified visually, or by the use of simple tests. An example might be a metal object made of a silvery-colored metal, such as a coin. It may be pure silver (in practice, a silver alloy containing more than about 95% silver), or it could be a silver-rich alloy that still has a silver appearance (silver coins with up to 30% copper can still look silvery, in which case the precise composition may well... 

Two grams of MgPz dissolved in 18 mL of trifluoroaceticacid for 3 hours at room temperature under nitrogen. Then reaction mixture was dropped on to ice and neutralized with ammonia and stood in refrigerator for about 2 hours. After then, it was taken into chloroform phase and washed and then, was dried with Na SO. Then, Solvent was removed and the precipitate was washed with MeOH. Finally, the violent color metal-free porphyrazine was obtained. Yield 1.76 g (80%) as given in Scheme 44.1. 

This ion is a chemical component released during volcanic eruptions. However, most contamination is of industrial origin, resulting mainly from the processing of the colored metal ores. 

Mercury is the only metal that is in a liquid state at room temperatures and remains liquid at temperatures well below the freezing temperature of water. Mercury is a noncombustible, heavy, silvery-colored metal that evenly expands and contracts with temperature and does not wet or stick to glass, which makes it ideal as a liquid for thermometers. Mercury is slightly volatile and will give off toxic fumes, especially if heated. Its has a unique melting point of —38.83°C, a boiling point of 3,56.73°C, and a density of 13.5336 g/cm. ... 

The clearance of DTPA metal complexes by the glomeruli is primarily dependent of the ligand. Thus, other metal complexes may also be useful for GFR measurements. For example, colored metal complexes that are exclusively excreted... 

Copper (Cu) is a bright brown-colored metal. When Cu powder or wire is heated in a high-temperature flame, its characteristic blue-colored emission is observed. Thus, Cu particles are commonly used as a component of aerial shells of fireworks. 

Because various swinging bucket centrifuges behave differently with respect to acceleration and braking, some optimization of centrifugation conditions may be advisable. This can be readily accomplished by UV and visible spectrophotometry if one uses BSA (or some other inexpensive protein sample) along with a small amount of dichromate as a yellow colored metal ion species. 

Physical Form. Hard, shiny, ductile stainless steel-colored metal or dull gray powder... 

Glass color Metal Ionic form environment... 

TetranitTo-lt5-dibydroxyanthraquinone or 2,4,6,8 -T etranitro-antbrarufin, HO.C6H(N02)2CCO)2C(SH(N02)2.0H yel plates (from fuming HNO3), mp not reported forms colored metallic salts (Refs 1 " 7)... 

In the light of the above discussion, it is necessary to redefine the criteria useful for describing catalytic activity. The coordination atmosphere of any given metal may be expected to affect the catalytic activity by influencing the solubility of the metal. If the metal complex, added to the reactant solution, can be replaced by thiyl entities, colored metal-thiol complexes may be produced, and the rate of reaction in all cases should correspond to Case 3 for adding simple metal salts (Table II). If the metal complex cannot be replaced, the rate of reaction may be quite different and will depend on the ease with which an electron... 

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