Question

(12) Co(en)Cl2 is green. When dissolved in water, the chloro ligands slowly hydrolyze and the solution gradually turns red. Paramagnetism is observed both before and after hydrolysis, but is weaker after hydrolysis. (a) Explain the change in color and paramagnetism described above. (b) If AgNO3 is added to a solution of Co(en)2Cl2, no precipitate is observed. However, after the complex is hydrolyzed, adding AgNO3 causes a precipitate to appear. Explain this observation. (c) Sketch all the possible geometric isomers of Coſen)Cl2. Indicate if optical isomerism is also possible for any of the geometric isomers.

Answer 1

by when we add Agnez in [cocendaCl₂] there is no precipitute occur because all că are inco-ordinated sphere not in ionization sphere [cocendaela] + AgNO3 → No pets → But after hydroalisis [ cocon, (140%2Cl₂ complex is termed here cł im is in lonization sphere therefore 2 mol Agno, is formed [Cocond (H₂O)₂] Cl₂ +AgNO3 [cocem (thes] (NO3)2 + 2 Ag cl white pets 9 [cocon, has three possible Stereo isomer +3 Nike 택 3- Ct26 NH N chy Minor el 1 cl ! 0 CHE HN 4K CHANN cth thN ↑ NHL ! IN With eth i ah - The cis cd-form) -CS 1. Nieth cth thN 2 KM i eth ciscal-form) a trems (meso)

Que ;-[u] Ans:- [cocen),c|2] where co is cote CA? CAD 3d7 45° upo 4dº 11/21/1171] O ID MID ► here ci is week ligand therefore solaning So electron pairing is not occur. Cot? [Ar]: 37 as 40 ad 12140111 xx xx xx] x x x x ID SP²d² hybridization [cocendaCl2] - here unpaired electron m=3 i magnetic moment i = nomir B.M = 13(3+2) B.m = 3.87 B.M here splitiny is smaller thus le low energy visibe light absorb that is highey gave length light ► 2h . [co conda(10),] cl2 hore to is co to in this complex ho is stronges lingana than cī these for more spliting is occur thats Ao <Paining cot?: [Ar 3d7 as 40 ad Plachen I O D 0 - here in this compled unpaired electron nal a Magnetic moment u = JacHROB.14 = 1.73 B.M these spliting is higher this & high energy visibal light absorb e that is low wave Length light)