Since then further compounds (" alkalides") containing anions of all other alkali metals except Li and Fr, as well as that of Ba, have been prepared. The synthesis of a crystalline salt of the sodium anion Na − was reported in 1974. The common notions that "alkali metal ions (group 1A) always have a +1 charge" and that "transition elements do not form anions" are textbook errors.Sodium, potassium, rubidium, caesium, barium, platinum, gold Within each category, elements can be found with one or two properties very different from the expected norm, or that are otherwise notable. Why, for example, was manganese such a bad conductor of electricity, when the elements on either side of it were reasonably good conductors? Why was strong magnetism confined to the iron metals? And yet these exceptions, I was somehow convinced, reflected special additional mechanisms at work. in the periodic table, anomalies too-some of them profound. Others count some of the metalloids as post-transition metals. Some authors count metalloids as nonmetals with weakly nonmetallic properties. Metalloids, straddling the metal-nonmetal border, are mostly distinct from either, but in a few properties resemble one or the other, as shown in the shading of the metalloid column below and summarized in the small table at the top of this section.Īuthors differ in where they divide metals from nonmetals and in whether they recognize an intermediate metalloid category. The characteristic properties of metals and nonmetals are quite distinct, as shown in the table below. Metalloids Tellurium, described by Dmitri Mendeleev as forming a transition between metals and nonmetals Specialized subcategories such as the refractory metals and the noble metals also exist. From left to right in the periodic table, these categories include the highly reactive alkali metals the less-reactive alkaline earth metals, lanthanides, and radioactive actinides the archetypal transition metals and the physically and chemically weak post-transition metals. Metals comprise the large majority of the elements, and can be subdivided into several different categories. Au, Pt), or have nonmetallic structures ( Mn and Ga are structurally analogous to, respectively, white P and I). Ti, Re), or are noble (hard to oxidise, e.g. W, Nb), are liquids at or near room temperature (e.g. Be, Al) or very high melting points (e.g. Some metals appear coloured ( Cu, Cs, Au), have low densities (e.g. Most metals are silvery looking, high density, relatively soft and easily deformed solids with good electrical and thermal conductivity, closely packed structures, low ionisation energies and electronegativities, and are found naturally in combined states. References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Lange's Handbook of Chemistry (1952), CRC Handbook of Chemistry & Physics (18th Ed.Metals appear lustrous (beneath any patina) form mixtures ( alloys) when combined with other metals tend to lose or share electrons when they react with other substances and each forms at least one predominantly basic oxide. Mercury is obtained from cinnabar by heating the cinnabar in air and condensing the vapor.Īppearance: heavy, silvery-white metal that is liquid at room temperature Sources: Mercury rarely occurs free in nature. Many of the salts and organic mercury compounds are important. Mercury is used to make thermometers, diffusion pumps, barometers, mercury vapor lamps, mercury switches, pesticides, batteries, dental preparations, antifouling paints, pigments, and catalysts. Uses: Mercury is amalgamated with gold to facilitate the recovery of gold from its ores. The concentration, and thus the danger, increases at higher temperatures. When room temperature air (20☌) is saturated with mercury vapor, the concentration greatly exceeds the toxic limit. Mercury is readily absorbed across unbroken skin or though the respiratory or gatroinstentinal tract. Mercury and its compounds are highly poisonous. An electrical discharge will cause mercury to combine with the noble gases argon, krypton, neon, and xenon. Mercury readily forms alloys with other metals, called amalgams. It is a relatively poor conductor of heat, but a fair conductor of electricity. Mercury is one of the few elements that is liquid at ordinary room temperatures. Properties: Mercury has a melting point of -38.842☌, boiling point of 356.58☌, specific gravity of 13.546 (20☌), and a valence of 1 or 2. Word Origin: from the Planet Mercury Hg is the symbol for Hydrargyrum, which means liquid silver Mercury has been found in Egyptian tombs dating to 1500 B.C.Įlectron Configuration: 4f14 5d10 6s2 Mercury (Hydrargyrum) Atomic Number: 80ĭiscovery: Known to the ancient Hindus and Chinese. Mercury is metal and one out of the rest of the elements, it is a liquid at room temperature.
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