元素的地球化学亲和性PPT课件

To first order, the distribution of elements between core and mantle resembles equilibrium partitioning between metal liquid and silicates…confirmed by iron and achondrite meteorites (but at high P, no separate sulfide phase) achondrite [ei'kɔndrait] n. 不含球粒陨石
Electron affinity is a measure of an atom’s ability to form negative ions.
atom(g) + e- + EA ion-(g)
Electron Affinities of Main Group Elements
电负性＝电离势＋电子亲和能 相对值
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Siderophile
Generally concentrate in ironrich melt
Chalcophile
Generally occurs with sulfur
Atmophile
Generally found in the atmosphere
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元素结合规律可从两个角度来衡量
1、 F的电负性最大,电负性大的元素集中在周期表的右 上角; Cs(Fr) 的电负性最小,电负性小的元素集中在周 期表的左下角.
2、如果原子吸引电子的趋势相对较强, 元素在该化合 物中显示电负性(electronegative);如果原子吸引电子的 趋势相对较弱,元素在该化合物中则显示电正性 (electropositive).
Electronegativity电负性
Electronegativity is a measure of the relative tendency of an atom to attract electrons to itself when chemically combined with another element.
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Geochemical Affinity
• In the classification scheme of Goldschmidt, elements are divided according to
how they partition between coexisting silicate liquid, sulfide liquid, metallic
liquid, and gas phase…defined by examining ore smelting slags and meteorites
• Melting a chondrite gives 3 immiscible(不能混合的)
Gas Phase
liquids pAlutsmvoappohr:ile
Behavior of elements: Goldschmidt’s classification
Elements divided into four broad categories:
Lithophile
generally found within crust and mantle Concentrate in silica-rich melts
– Fluorine is the most electronegative element.
– Cesium and francium 钫 are the least electronegative elements.
4 电负性( electronegativity)
元素的电负性：处于化合物中的该元素原子对电子 对的吸引能力.
No 1.从能量的角度 电负性（X） (Electronegativity): 原子在其外层吸引其他电子的能力
Image电离势（I） 电子亲和能（E）、
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电负性
Ionization Energy（电离能/势）
First ionization energy (IE1)
The minimum amount of energy required to remove the most loosely bound electron from an isolated gaseous atom to form a 1+ ion.
H, He, N, Noble gases
Silicate Liquid
Lithophile
Alkalis, Alkaline Earths, Halogens, B, O, Al, Si, Sc, Ti, V, Cr, Mn, Y, Zr, Nb, Lanthanides, Hf, Ta, Th, U
atom(g) + energy ion+(g) + e-
Ionization Energies in kJ/mol
Electron Affinity(电子亲和能）
Electron affinity is the amount of energy absorbed when an electron is added to an isolated gaseous atom to form an ion with a -1 charge.
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自然I界m的ag 元e 素结合Im类age 型及特点
自然界元素结合分两种：
同种或性质相似元素结合--非极性键，一般形成 共价键；
异种元素结合--极性键，一般形成离子键。
自然界元素结合特点：
多键性和过渡性；
自然界形成的化合物（矿物）都是不纯的，每一 种矿物都构成一个成分复杂、含量变化的混合物 系列。
Sulfide Liquid Metallic Liquid
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Chalcophile Siderophile
Cu, Zn, Ga, Ag, Cd, In, Hg, Tl, As, S, Sb, Se, Pb, Bi, Te
Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt, Mo, Re, Au, C, P, Ge, Sn