General

Question 1

What are transition metals?

Answer 1

These are metals that have partially filled d orbitals or form ions with partially filled d orbitals

Question 2

What is pairing energy?

Answer 2

The energy required to place 2 electrons in one orbital. This requires energy as this causes repulsions.

Question 3

Describe the order of occupation of orbitals

Answer 3

1s, 2s, 2p, 3s, 3p, 4s, 3d 4p

The 3d orbital is higher in energy than the 4s orbital
4s is filled first and empties first

Question 4

What energy to the 3d orbitals have in relation to each other?

Answer 4

They are degenerate

This means they all have the same energy

Question 5

Which elements do not follow the filling orbital rules?

Answer 5

Cr has the electron configuration: 3d54s1
Cu has the electron configuration: 3d104s1

One of the s electrons have moved into the d orbitals
This is because this maximise angular momentum and avoids repulsions in the 4s orbital from pairing energy

Question 6

What are the 5 d orbitals?

Answer 6

dyz, dxy, dxz, dz2 and dx2-y2

Question 7

Why are d orbitals bad at shielding?

Answer 7

They are bad at shielding valence electrons due to their shape

Question 8

Why is Zn not considered a transition metal?

Answer 8

Zn and Zn2+ both have d10 configuration which means it’s d orbitals are completely filled
Therefore it is not considered a transition metal

Question 9

Describe the trend in ionisation energy

Answer 9

Increase from Ca to Cr (d1-d4) as an electron is removed from singly occupied orbitals
Decrease at Mn (d5) as electron has been removed from doubly occupied orbital
Increase from d6-d10

Question 10

Why is there a difference in energy between d1-d5 and d6-d10

Answer 10

There is a difference in energy due to pairing energy

Question 11

Why are doubly occupied orbitals easier to remove from?

Answer 11

The electrons in doubly filled orbitals will experience repulsions and so less energy is required to remove them

Question 12

Describe the trend in atomic radius

Answer 12

The atomic radius from Li-F decreases due to increase in zeff
Anomalous increase at Mn- double filled orbital as repulsion are more significant than zeff therefore radius increases

Question 13

Describe the trend in orbital size

Answer 13

As n increases, orbital size increases

Question 14

What is the lanthanide contraction?

Answer 14

D orbitals are poor at shielding so they cause anomalous trends in atomic orbital size

Question 15

What is a metal complex?

Answer 15

This is a Lewis acid which acts as a central metal ion with a number of Lewis bases which are the ligands

Question 16

What is a donor atom?

Answer 16

This is the atom in the ligand that forms the bond to the central metal atom by donation of a pair of electrons

Question 17

What is coordination number?

Answer 17

This is the number of ligand donor atoms to which the central metal atom is directly bonded

Question 18

Describe the elemental abundances in the earths crust, the sea, and the human body

Answer 18

Earths crust- lots of Fe
Sea water- even distribution
Human body- lots of transition metals- higher conc- as many TM are biologically necessary

Question 19

Describe the applications of transition metals

Answer 19

• structural materials- Fe alloyed with Cr, V, MO, Ni, Ti
• electrical conductors- cu
• Batteries- MnO2, Ni, Zn
• magnetic materials- Fe+, Co, Ni, Fe2O3 or CrO2
  Catalyst- Co, Cu
  Pharmaceuticals
  Pigments

Question 20

What is a chelate?

Answer 20

A complex containing a polydentate ligand is called a chelate

Question 21

What is a chelating ligand?

Answer 21

Polydentate ligands are collectively known as chelating ligands

Question 22

What factors determine coordinating number?

Answer 22

1) The size of the central atom (large means more ligands)
2) the steric interactions between the ligands
3) the electronic interactions

Question 23

What charge can coordination complexes have ?

Answer 23

They can be neutral or a salt

Question 24

What charge can ligands have?

Answer 24

They can be neutral or anionic

Question 25

How do you write the formula of a complex?

Answer 25

Formula in square brackets
Metal ion first then anionic ligands and then neutral ligands
Cations come before anions

Question 26

How do you name a complex?

Answer 26

Ligands in alphabetical order
Then name of central atom with charge of complex 
Prefix is number of ligands 
Stereochemical descriptors at the start
Anionic complexes end in ate