(c) Aqueous solutions of Co2+ salts are pale pink. They contain the complex ion [Co(H₂O)]2+. Addition of concentrated HCl results in a profound colour change to dark blue, due to formation of [CoC14]2. The main absorption bands of [Co(H₂O)6]2+ and [CoC14] occur at 19400 cm¹ (~ 10 M¹ cm) and 14700 cm¹ (~ 1000 M¹ cm¹), respectively. (i) Explain the difference in the transition energies between the two complexes. (ii) Explain why the absorption band of [CoC14]2 is much more intense than that of [Co(H2O)%]2*. (d) Calculate the ligand field stabilisation energy of the following complexes: (i) [Mn(H₂O)6]2+ (ii) [Fe(CN)6]³- (iii) [CoC14]²-

(c) Aqueous solutions of Co2+ salts are pale pink. They contain the complex ion [Co(H₂O)]2+. Addition of concentrated HCl results in a profound colour change to dark blue, due to formation of [CoC14]2. The main absorption bands of [Co(H₂O)6]2+ and [CoC14] occur at 19400 cm¹ (~ 10 M¹ cm) and 14700 cm¹ (~ 1000 M¹ cm¹), respectively. (i) Explain the difference in the transition energies between the two complexes. (ii) Explain why the absorption band of [CoC14]2 is much more intense than that of [Co(H2O)%]2*. (d) Calculate the ligand field stabilisation energy of the following complexes: (i) [Mn(H₂O)6]2+ (ii) [Fe(CN)6]³- (iii) [CoC14]²-

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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