What is the coordination number for each of the following complexes or compounds? a) [fe(cn)4(co)2]2âb) [cr(edta)]âc) [zn(nh3)4]2+d) [ag(nh3)2]no3

A) [Fe(CN)₄(CO)₂]²⁻: coordination number = 6.

B) [Cr(EDTA)]⁻: coordination number = 6.

C) [Zn(NH₃)₄]²⁺: coordination number = 4.

D) [Ag(NH₃)₂]NO₃: coordination number = 2.

Explanation:

A) [Fe(CN)₄(CO)₂]²⁻:

In this complex, Fe is bonded with 4 molecules of CN (with 4 coordinate bonds, one bond for each molecule) and 2 molecules of CO (with 2 coordinate bonds, one bond for each molecule) forming the complex with 6 coordinate bonds.

coordination number = 6.

B) [Cr(EDTA)]⁻:

In this complex, Cr is bonded with 1 molecules of EDTA (with 6 coordinate bonds, 4 O atoms and 2 N atoms in EDTA molecule).

coordination number = 6.

C) [Zn(NH₃)₄]²⁺:

In this complex, Zn is bonded with 4 molecules of NH₃ (with 4 coordinate bonds, one bond for each molecule).

coordination number = 4.

D) [Ag(NH₃)₂]NO₃:

In this complex, Ag is bonded with 2 molecules of NH₃ (with 2 coordinate bonds, one bond for each molecule).

coordination number = 2.

the electronic configuration of an atom with eight electrons is 1s²2s²2p⁴. the orbital diagrams are shown in the figure.

as per the hunds rule:

1. electrons tend to avoid being in the same orbital as per as practicable.

2. electrons in different orbitals of the same energy will have their spin parallel.

this can be illustrated from the multiplicity of the orbitals of the atom. as there are four electrons in the p orbital and p orbital has 3 sub-shells. the electrons can be fed in different ways as shown in the figure but the correct orbital diagram will be as per the hunds rule.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.