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

c is the answer because when something is left after something evaporates that shows the chemical change.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.