Antimony physical properties

Solders. In spite of the wide use and development of solders for millennia, as of the mid-1990s most principal solders are lead- or tin-based alloys to which a small amount of silver, zinc, antimony, bismuth, and indium or a combination thereof are added. The principal criterion for choosing a certain solder is its melting characteristics, ie, soHdus and Hquidus temperatures and the temperature spread or pasty range between them. Other criteria are mechanical properties such as strength and creep resistance, physical properties such as electrical and thermal conductivity, and corrosion resistance. 

The physical properties of bismuth, summarized ia Table 1, are characterized by a low melting poiat, a high density, and expansion on solidification. Thermochemical and thermodynamic data are summarized ia Table 2. The soHd metal floats on the Hquid metal as ice floating on water. GaUium and antimony are the only other metals that expand on solidification. Bismuth is the most diamagnetic of the metals, and it is a poor electrical conductor. The thermal conductivity of bismuth is lower than that of any other metal except mercury. 

Arsenic, Antimony and Bismuth Table 13.4 Some physical properties of Group 15 elements... 

T ble 13.6 Some physical properties of the trihalides of arsenic, antimony and bismuth... 

Some Physical Properties of Antimony and Bismuth Chalcogenide Halides... 

Antimony dichloride trifluoride, 3 62t Antimony dioxide, 3 59 Antimony graphite fluoride, 3 63-64 Antimony halides, physical properties of, 3 61t... 

Antimony pentachloride, 3 64 11 862 physical properties of, 3 6 It Antimony pentachloride bisCiodine chloride), 3 62t... 

Antimony tetroxide, 3 59 Antimony tribromide, 3 63 physical properties of, 3 6 It Antimony trichloride, 3 60-61 physical properties of, 3 6 It Antimony trichloride aniline, 3 62t Antimony trichloride bisacetone, 3 62t Antimony trichloride diethyl ether,... 

Chromium(III) acetylacetonate, physical properties, 6 528t Chromium alloys, 6 468-523 Chromium alumina pink corundum, formula and DCMA number, 7 347t Chromium antimony titanium buff rutile, formula and DCMA number, 7 347t Chromium-based catalysts, 20 173 Chromium baths, 9 800-804... 

Balazs, G. Breunig, H. J. Supramolecular Interactions in Structures of Organic Antimony and Bismuth Compounds. In Unusual Stuctures and Physical Properties in Organometallic Chemistry Gielen, M., Willem, R., Wrackmeyer, B., Eds. Wiley Chichester, 2002 pp 387-111. 

Physically, antimony s properties are related to sulfur and some of the nonmetals, but chemically, its properties are related to metals. It behaves like a metal and is often found in nature along with other metals. In its pure form it is rather hard and britde with a grayish crystal structure... 

AUatropes. Some or the elements exist in two or more modifications distinct in physical properties, and usually in some chemical properties. Allotropy in solid elements is attributed to differences in the bonding of the atoms in the solid. Various types of allotropy are known. In ertuntiomorphic allotropy, the transition from one form to another is reversible and takes place at a definite temperature, above or below which only one form is stable, e.g., the alpha and beta forms of sulfur. In dynamic alloimpy. the transition from one form to another is reversible, but with no definite transition temperature. The proportions of the allotropcs depend upon the temperature. In monotropic allotropy, the transition is irreversible. One allotrope is mctastable at all temperatures, e.g.. explosive antimony. 

The compounds have been of interest because of their physical properties. They are both photoconducting and ferroelectric. Antimony(III) iodide sulfide has a Curie point at 22°C.12... 

Although the elements, gold (Au), silver (Ag), tin (Sn), copper (Cu), lead (Pb), mercury (Hg), antimony (Sb), arsenic (As), carbon (C), iron (Fe), sulfur (S) and zinc (Zn) had been known since ancient times, the first scientific discovery of an element occurred in 1669, when Hennig Brand discovered phosphorus (P). During the next two hundred years various chemical and physical properties of elements and their compounds were studied by chemists. By 1869, a total of 63 elements had been discovered. As the number of known elements increased, scientists began to recognize patterns in properties and began to develop classification schemes. 

Pure lead has low creep and fatigue resistance, but its physical properties can be improved by the addition of small amounts of silver, copper, antimony, or tellurium. Lead-clad equipment is in common use in many chemical plants. The excellent corrosion-resistance properties of lead are caused by the formation of protective surface coatings. If the coating is one of the highly insoluble lead salts, such as sulfate, carbonate, or phosphate, good corrosion resistance is obtained. Little protection is offered, however, if the coating is a soluble salt, such as nitrate, acetate, or chloride. As a result, lead shows good resistance to sufuric acid and phosphoric acid, but it is susceptible to attack by acetic acid and nitric acid. 

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