A2 chemistry transition metals revision sheet

Mathsandscience.net Copyright 2010 Tutoring for AS and A2 Mathsandscience.net Transition metals revision sheet (version 6). Sc and Zn are not transition metals , they do not have partially filled d subshells The electron configuration can be written [Ar]4s2 3d2 titanium as an example. Variable oxidation state, loose 4s electrons first. Higher oxidation state ,act as an oxidising agent. All transition metals in ionic state are coloured d shell electrons absorb specific light frequency. Light not absorbed is reflected giving colour. Co2+ ions are pink, form blue ppt Co(OH)2 Fe2+ ions are pale green in solution forms green ppt Fe(OH)2 which turn brown on contact with air. Fe3+ ions are pale yellow in solution forms rusty brown ppt Fe(OH)3 Catalytic reactions. Surface adsorb on desorbed after. Variable oxidation state creates intermediates. Haber Process iron metal catalyst, contact process formation of SO3 form SO2 V2O5 catalyst. Hydrogenation of Alkenes nickel metal catalyst Decomposition of hydrogen peroxide: Catalyst: Manganese(IV)Oxide(lab production of Oxygen) Complex ions: Form Six Coordinate Bonds with water and Ammonia Only 4 with Chlorine ion as it is big and Charged [Fe(H20)6]2+ Octahedral shape [FeCl4]2-[FeCl2(H20)4] Can form Cis trans Isomer. H20 and NH3 Rae monodentate (1 coordinate bond) Ethane 1,2 diamine (EN)is bidentate(two coordinate bonds. Ethylenediaminetetraacetic acid EDTA is hexadentate(six coordinate bonds) Ligand substitution: ammonia added to copper ions. [Cu(H20)6]2+ light blue form a light blue ppt first! [Cu(OH)2 ] then exess ammonia produces [Cu(NH3)4(H20)2] 2+ which is a dark blue solution. Reaction of Copper(II) and HCL. From blue [Cu(H20)6]2+ to green to yellow(CuCl42-) this is in equilibrium and reversible Reaction of Cobolt(II) and HCL. From pink [Co(H20)6]2+ to Blue (CoCl42-) this is in equilibrium and reversible Haemoglobin has 4 heam groups each containing an Fe2+ ion four bonds to amine group one to Globlin protein and one to Oxygen Kstab [Co(H20)6]2+ + 4Cl-CoCl42-+6H2O Kstab= [ CoCl42-] Note: 6H2O is not part of Kstab [Co(H20)6]2+ [Cl-]4