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Germanium cluster anions (Zintl ions) such as Ge 4 2−, Ge 9 4−, Ge 9 2−, [(Ge 9) 2] 6− have been prepared by the extraction from alloys containing alkali metals and germanium in liquid ammonia in the presence of ethylenediamine or a cryptand. [40] [42] The oxidation states of the element in these ions are not integers—similar to the ...
Amorphous metallic glasses are generally most easily prepared if one of the components is a metalloid or "near metalloid" such as boron, carbon, silicon, phosphorus or germanium. [ 173 ] [ n 20 ] Aside from thin films deposited at very low temperatures, the first known metallic glass was an alloy of composition Au 75 Si 25 reported in 1960. [ 175 ]
Lists of metalloids differ since there is no rigorous widely accepted definition of metalloid (or its occasional alias, 'semi-metal'). Individual lists share common ground, with variations occurring at the margins. The elements most often regarded as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium.
Its thermal conductivity (2,200 W/m•K) is five times greater than the most conductive metal (Ag at 429); 300 times higher than the least conductive metal (Pu at 6.74); and nearly 4,000 times that of water (0.58) and 100,000 times that of air (0.0224). This high thermal conductivity is used by jewelers and gemologists to separate diamonds from ...
Germanium makes up 2 parts per million of the Earth's crust, making it the 52nd most abundant element there. On average, germanium makes up 1 part per million of soil. Germanium makes up 0.5 parts per trillion of seawater. Organogermanium compounds are also found in seawater. Germanium occurs in the human body at concentrations of 71.4 parts ...
Two oxides of germanium are known: germanium dioxide (GeO 2, germania) and germanium monoxide, (GeO). [4] The dioxide, GeO 2 can be obtained by roasting germanium disulfide (GeS 2) or by allowing elemental germanium to slowly oxidze in air, [5] and is a white powder that is only slightly soluble in water but reacts with alkalis to form germanates. [4]
As a metalloid the chemistry of silicon is largely covalent in nature, noting it can form alloys with metals such as iron and copper. The common oxide of silicon (SiO 2) is weakly acidic. Germanium. Germanium is a shiny, mostly unreactive grey-white solid with a density of 5.323 g/cm 3 (about two-thirds that of iron), and is hard (MH 6.0) and ...
Around 330 BCE, the Greek philosopher Aristotle proposed that everything is made up of a mixture of one or more roots, an idea originally suggested by the Sicilian philosopher Empedocles. The four roots, which the Athenian philosopher Plato called elements, were earth, water, air and fire.