red-orange metallic luster 二、the simple substance 1.Physical properties: Cu:red,Ag:white,Au:yellow, 常温下都是面心立方晶体(face-centered cubic crystal),由于ns和(n-1)d上的一个 或几个电子都能参与成键,所以它们的熔沸 lustrous white metal 点较高,导电、导热性能好,有良好的延展 性,特别是金(Au),1克金能抽成长达3km 的金丝,或压成厚约100nm的金箔。 它们都能形成合金(aloy):黄铜 metallic yellow (brass)(60%Cu,40%Zn),青铜 (bronze)(90%Cu,10%Sn),铜币 (copper”coin)(95%Cu,5%Al),银 币(“silver'”coin)(80%Cu,20%ni)
二、the simple substance 1. Physical properties: Cu: red, Ag: white, Au: yellow, ¾ 常温下都是面心立方晶体(face-centered cubic crystal),由于ns和(n-1)d上的一个 或几个电子都能参与成键,所以它们的熔沸 点较高,导电、导热性能好,有良好的延展 性,特别是金(Au), 1克金能抽成长达3km 的金丝,或压成厚约100nm的金箔。 ¾ 它们都能形成合金(alloy):黄铜 (brass) (60% Cu,40% Zn),青铜 (bronze) (90% Cu,10% Sn),铜币 (“copper” coin) (95% Cu,5% Al) ,银 币(“silver” coin) (80% Cu,20% Ni) 16
Au 电子结构→颜色??? pale greenish vellow copper white red Ag Cu 1.5 Relativistic molecular structure 47 AND PLASMA PHYSICS The different colours of silver and gold provide perhaps the most notorious phenomenon in which relativistic effects have been implicated [88,p.583].The observed reflectivity of gold is high for photon energies less than about 2.4 eV.in the middle of the visible light spectrum but drops abruptly at higher I.P.Grant energies.This is attributed [93]to the onset of absorption by electrons in the 5d Relativistic Quantum band due to excitation to the Fermi level(essentially 6s in character).This is Theory of Atoms consistent with a calculated relativistic interband gap of 2.38 eV,whereas the and Molecules nonrelativistic estimate would have been much higher,pushing the absorption Theory and Computation edge to higher photon energy in the ultraviolet.Silver,in the previous row of the Periodic Table,has a smaller relativistic rise in the 4d energy and a smaller reduction of the 5s energy,shown qualitatively by the DHF and HF eigenvalues of Fig.1.12 and resulting in a relativistic absorption edge at around 3.7 eV in the ultraviolet.Thus "nonrelativistic gold"should appear white like silver,a conclusion supported by band structure calculations [88, References 359 b-k].It seems reasonable to assign much of the difference in properties of the two coinage metals to relativistic mechanisms.Pyykko [88 discusses similar examples in other groups of the Periodic Table 17
电子结构 颜色 ??? 17
2.Chemical properties: IVB VIIⅢ IB IIB IIIA Al Z显著,主导 Ti Cu Zn Ga r,次要 Zr Ag Cd In ∴.金属性渐弱 Hf Au Hg Ti (周期性)
2. Chemical properties: IVB . VIII IB IIB IIIA Al Z* 显著↗,主导 Ti Cu Zn Ga r ↗,次要 Zr Ag Cd In ∴金属性渐弱 Hf Au Hg Tl (周期性) 18
(1)与02反应: hot-red 2Cu+0, Cuo 更高温度 4Cu+02 2Cu20 在潮湿空气中: 2Cu+O2+H0+C02=CuC03Cu(OHD2(灰绿色) 19
(1) 与O2反应: 在潮湿空气中: 19
(2)与酸反应: >铜族元素的标准电极电势均为正值(在氢以后),所以不能置换 稀酸中的氢。但当有空气存在时,Cu可缓慢溶解于这些稀酸中: 2Cu 4HCI +O,=2CuCl,+2H2O 2CU+2H2S04+O2=2CuS04+2H2O >浓盐酸在加热时也能与Cu反应,这是因为C和Cu+形成配离子: 2Cu 8HCI()=2H3[CuCl4]+H2 >Cu与浓H,S04,HNO3反应 Cu+4N03w=Cu0N03)2+2NO2↑+2H20 >Ag与热、浓H,S0,和浓HNO3反应 Ag+2HNO3(AgNO3 +NO2 +H2O >Au可溶于饱和Cl,的盐酸中或王水(aqua regia)中 2Au+3Cl,+2HCI=2HAuCl Au+4HCI+HNO:=HAuCI +NO+2H,O K稳(AuCL4)上1X1026四氯合金(II)酸(强酸) 20
(2) 与酸反应: Au 4HCl HNO HAuCl NO 2H O 2Au 3Cl 2HCl 2HAuCl 3 4 2 2 4 ¾ Cu与浓H2SO4,HNO3反应 ¾ Ag与热、浓H2SO4和浓HNO3反应 ¾ Au可溶于饱和Cl2的盐酸中或王水(aqua regia)中 K稳(AuCl4 - )= 1×1026 四氯合金(III)酸 (强酸) ¾ 浓盐酸在加热时也能与Cu反应,这是因为Cl- 和Cu+形成配离子: 2Cu + 8HCl(浓) = 2H3[CuCl4] + H2 ¾ 铜族元素的标准电极电势均为正值(在氢以后),所以不能置换 稀酸中的氢。但当有空气存在时,Cu可缓慢溶解于这些稀酸中: 2Cu + 4HCl + O2 =2CuCl2 + 2H2O 2Cu + 2H2SO4 + O2 =2CuSO4 + 2H2O 20