Química de Coordenação

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23 Transition Metals and Solutions to Exercises Coordination Chemistry (e) 6, +3; 6 O. is a bidentate ligand; each ion is bound through 2 atoms for a total of 6 donor atoms. (f) 4, +2; 4 N. en is a bidentate ligand bound through 2 N atoms. 23.26 (a) Coordination number = 6, oxidation number = +3; 6 C (see Solution 23.25(d)) (b) 4, +2; 4 (c) 6, +4; 6 N. en is a bidentate ligand bound through N, for a total of 6 N donors. (d) 6, +3 ; 4 N, 2 O. en is a bidentate ligand bound through N, for a total of 4 N donors. is bidentate with 2 donors. (e) 6, +3; 6 N. When thiocyanate is written "NCS," it is bound through N. This makes a total of 6 N donors. (f) 5, +2; 4 N, 1 I. bipy is bidentate bound through N, for a total of 4 N donors. Common Ligands in Coordination Chemistry (section 23.3) 23.27 (a) A monodendate ligand binds to a metal in through one atom; a bidendate ligand binds through two atoms. (b) If a bidentate ligand occupies two coordination sites, three bidentate ligands fill the coordination sphere of a six-coordinate complex. (c) A tridentate ligand has at least three atoms with unshared electron pairs in the correct orientation to simultanously bind one or more metal ions. 23.28 (a) 2 coordination sites, 2 N donor atoms (b) 2 coordination sites, 2 N donor atoms (c) 2 coordination sites, 2 donor atoms (Although there are four potential donor atoms in it is geometrically impossible for more than two of these to be bound to a single metal ion.) (d) 4 coordination sites, 4 N donor atoms (e) 6 coordination sites, 2 N and 4 donor atoms 23.29 Analyze/Plan. Given the formula of a coordination compound, determine the number of coordination sites occupied by the polydentate ligand. The coordination number of the complexes is either 4 or 6. Note the number of monodentate ligands and determine the number of coordination sites occupied by the polydentate ligands. Solve. (a) ortho-phenanthroline, is bidentate (b) oxalate, is bidentate (c) ethylenediaminetetraacetate, EDTA, is pentadentate (d) ethylenediamine, en, is bidentate 23.30 (a) 6 (b) 6 (c) 6 (d) 6 699