Coordination Chemistry and Reaction Mechanism — DU B.Sc (hons) Chemistry Previous Year Question Papers

7. (i) Describé the polarisation theory to explain the trans effect. are higher than the calculated values. Why? (i) For the complex [CrEO), 24the mean pairing energy P = 23500cm" and magnitude of A. = 13900 cm 5,5,5 (a) Will the complex exist in a high or low Spin arrangement? (b)' Write the electronic configuration of the complex ion. (C) Calculate CFSE of the complex in kJ mol!. (d) Will the complex be labile or inert? "* "i Will it have a regular geometry or a distorted geometry A complex is prepared by mixing CoC and NH, in the molar rațio of 1;4 A0,01 molal solution of this complex vas tound to freeze, at - 0.0372°C, What is the formula 1 of the complex and expected range of conductivity? Giver that the molal depression constant of water Kr = 1.86 °C/ (ii) Taking suitable'example, explain the macrocyclic effect on the thermodynamic stability of compléxes. (i)" A metal ion forms three complexes. [M(Br) 14, [MCN),14 and [M(H;O.)6*": The colours of the complexes are red green and blue, but not necessarily in 'the same order. Match the complexes with the appropriate colour and explain. ma wais 5,5,5 Chemistry and Reaction Time: 3 Hours Maximum'Marks: 90 1. (a) Write the name for the following complexes according to (b) Write the formula for the following complexes accordin (il) Sodium bis (thiosulphato) argentate. (1), (iv) Potassium pentachloridonitridoosmate (VI) (v) Tris(propane 1:2-diamine) cobalt (It) sulphate (c) A compound CoCl: 4NH, contains only one Clion that 40» «precipitates as AgCl on the addition of Ag ions. Based or Werner's coordination theory, give a brief explanation of i ole r'the observation. How was it concluded that the complex is octahedral? " 2g. r(i)a Dräw the mölecular orbital energy level diagram for o - bonding in the case of [Co(CN),1 octahedral. complex ion. Discuss the effect of metal to ligand pi bonding on "the 10 Dq.value. (i) Use CFT to explain the following. ta: , "a), letrahedral complexes are always high spin. (b) [Ti(H2O) 13* ion has purple colour., (iii) A complex, CoH, (H,O.);C, Br, exists in two isomeric forms, A and B. Form A gives two moles of AgBr when treated with AgNO,, while the other form yields one mole fAgBr. Give a proper explanation, identity the type o isomerism and write the structural formula of A and I 3. (i) Which geometrical isomer of [Cu(en) (H,O), 12+ is thermodynamically more stable and why ? Also, compare ,;and explain, its stability with the [CuNH), (H, 0),2*+ (ii) Draw a crystal field splitting diagram for.a z-out octahedral **. •'complex and explain that square planar complexés are an extreme case of Jahn-Teller distortion. (i) Which of the following complexes has a higher 10 Dq value and why? 4. (i), The magnetic moment value, of [Mn(CN" ion is 2:8 B.M. Predict the type of hybridisation of the central metal • '1 toni and lability of the complex according to VBT. a ( Using VBT, explain [NiCIl? is paramägnetic, but