Coordination Chemistry

Question 1

A coordination compound contains…

Answer 1

one or more complex ions in which a small number of molecules or ions surround a central metal atom or ion, usually from the transition metal family

Question 2

Lewis acids and bases state that:

Answer 2

Lewis acid accepts a pair of electrons i.e. an electron pair acceptor

Lewis base donates a pair of electrons i.e. an electron pair donor

Question 2

Arrhenius acids and bases state that:

Answer 2

Arrhenius acid - a substance that ionizes to produce H+ in aqueous solution

Arrhenius base - a substance that ionizes to
produce OH- in aqueous solution

Question 3

Bronsted-Lowry acids and bases state that:

Answer 3

Bronsted-Lowry acid is a proton (H+) donor
Bronsted-Lowry base is a proton acceptor

Question 4

How are ligands classified?

Answer 4

Each ligand is classified according to the number of donor atoms – in this case, each N in NH3 and each Cl- donates one pair of electrons, hence they are monodentate ligands.

Question 5

What is the coordination number?

Answer 5

The number of donor atoms bonded to the central metal ion in the complex

Question 6

Examples of monodentate ligands are:

Answer 6

H2O, H2S, HS-, CH3OH, CH3SH, F-, and OH-

Question 7

Examples of bidentate ligands can be:

Answer 7

oxalate ion (ox) = C2O42-
ethylenediamine (en) = NH2CH2CH2NH2
2,2’-bipyridine (bpy)

Question 8

If the geometry is linear, the coordination number is

Answer 8

2

Question 9

If the geometry is tetrahedral, the coordination number is

Answer 9

4

Question 9

If the geometry is square planar, the coordination number is

Answer 9

4

Question 10

The geometry is considered to be octahedral when…

Answer 10

If the coordination no is 6 the ligand donor atoms are arranged octahedrally around the metal ion (octahedral complex)

For 1st row d-block metal ions, coordination no = 6
(octahedral) is by far the most common