- C Aqueous Solutions Of Co2 Salts Are Pale Pink They Contain The Complex Ion Co H20 X 2 Addition Of Concentrated H 1 (61.09 KiB) Viewed 56 times
(c) Aqueous solutions of Co2+ salts are pale pink. They contain the complex ion [Co(H20)x]2+. Addition of concentrated HCl results in a profound colour change to dark blue, due to formation of [CoC14]?-. The main absorption bands of [Co(H2O).]2+ and (CoC14]? occur at 19400 cm(- 10 M'cm') and 14700 cm' (8 – 1000 M'cm'), respectively. (i) Explain the difference in the transition energies between the two complexes. [3 marks] (ii) Explain why the absorption band of [CoC14]?- is much more intense than that of [Co(H20)6]?+ [3 marks] (d) Calculate the ligand field stabilisation energy of the following complexes: (i) [Mn(H20).]2+ (ii) [Fe(CN)6] (iii) (CoC14]? [6 marks]