Discuss each of the following observations: (a) The [CoCl4]2– ion is a regular tetrahedron but [CuCl4]2– has a flattened tetrahedral structure. (b) The electronic absorption spectrum of [CoF6]3– contains two bands with maxima at 11,500 and 14,500 cm–1.

See explanation

Explanation:

a) Look at the electronic configuration of both species;

Cu^2+- [Ar]  3d9 4s0

Co^2+- [Ar]  3d7 4s0

We  can now see that a Jahn Teller effect occurs in [CuCl4]2– due to its d9 configuration. This  Jahn-Teller distortion causes the symmetry of  [CuCl4]2–  to change from tetrahedral  T

d  to trigonal pyramidal  C3v.

b) This is a consequence of Jahn-Teller effect in [CoF6]3– which makes the Co-F bonds lie along the z-axis and become elongated in comparison  to the remaining four Co-F bonds

answer: the rate of diffusion increases with increase in temperature.

increase in temperature, increases the molecular/particles speed (kinetic energy. diffusion means movement of particles through the material.

generally, the heavier the particle the more it interacts with the environment and more the temperature matters. so higher temperature results in higher diffusion.