siderophile การใช้

• It currently has only 2 members : the siderophile trace element concentrations.
• The currently accepted scientific hypothesis is that the Earth was formed by siderophile elements accumulated.
• Recent speculation suggests that the innermost part of the core is enriched in gold, platinum and other siderophile elements.
• Most siderophile elements have practically no affinity whatsoever for oxygen : indeed oxides of gold are thermodynamically unstable with respect to the elements.
• Because they are so concentrated in the dense core, siderophile elements are known for their rarity in the Earth's crust.
• By contrast, siderophile elements tend to bond with iron and other metals, which leads to high density and tendancy to be depleted near the surface.
• Sulfur is strongly siderophile and only moderately volatile and depleted in the silicate earth; thus may account for 1.9 weight % of Earth's core.
• Thus, siderophile elements are bound through metallic bonds with iron in the dense layer of the Earth's core where pressures may be high enough to keep the iron solid.
• Several transition metals, including chromium, molybdenum, iron and manganese, show " both " lithophile " and " siderophile characteristics and can be found in both these two layers.
• However, because they are concentrated in the mantle and core, siderophile elements are believed to be present in the Earth as a whole ( including the core ) in something approaching their solar abundances.
• This has led to their depletion in the Earth's crust relative to their solar abundances, though because the minerals they form are nonmetallic, this depletion has not reached the levels found with siderophile elements.
• In 2014, analysis of the concentration and distribution of siderophile elements as well as the size of the area where the impact melted the rock indicated that a comet rather than an asteroid most likely caused the crater.
• Gold, a siderophile, is most commonly recovered by dissolving the ores in which it is found in a reactive than gold, displaces the gold : 2 [ Au ( CN ) 2 ] + Zn ?
• Analysis showed it to be about 90 % iron and 5 % nickel, with the rest consisting of various elements, including copper, cobalt, and 6 siderophile element implied that the Wabar site was a meteorite impact area.
• They were further rarefied in the crust by being siderophile ( iron-loving ) elements, in the Goldschmidt classification of elements, and have thus been depleted from the crust by being relocated into the Earth's core.
• Siderophile ( from " sideron ", " iron ", and " philia ", " love " ) elements are the high-density transition metals which tend to sink into the core because they dissolve readily in iron either as solid solutions or in the molten state.