Topic 15 - Transition metals
Transition metals
Define a transition metal
a transition metal is a d-block element which forms one or more stable ions
and incompletely filled d-orbitals
Describe the general physical and chemical properties of transition metals
physical - similar atomic radii, high densities and high melting and boiling points
chemical-
they form complexes
they form coloured ions in solution
variable oxidation states
good catalysts
Write the electronic configurations of Ar, Sc, Ti, Ni and V
Ar - 1s2 2s2 2p6 3s2 3p6
Sc - 1s2 2s2 2p6 3s2 3p6 4s2 3d1
Ti - [Ar] 4s2 3d2
Ni - [Ar] 4s2 3d8
V - [Ar] 4s2 3d3
Explain why Sc and Zn aren't transition metals
Scandium only forms one ion, Sc3+ which has an empty d sub-shell
Zinc only forms one ion Zn2+ which has a full d sub-shell
State and explain the electronic configuration of Chromium and copper
Chromium - [Ar]4s1 3d5
is it not [Ar]4s2 3d4 , because is it more stable if one of the 4s electrons is in the
3d orbital, so that each 3d orbital contains one unpaired electron
Topic 15 - Transition metals 1
, Copper - [Ar]4s1 3d10
it is not [Ar]4s2 3d9 , because it is more stable if the 3d subshell is completely
filled
State the formula of the ions and colour of the different oxidations of
vanadium
Complex ions
What are complex ions?
complex ions are metal ions surrounded by dative covalently bonded ligands
Define a ligand
ligand is an atom or ion or molecule that donates a pair of electrons to a central
mental atom/ion
a ligand must have at least one lone pair of electrons to form a dative covalent
bond with
Monodentate ligand - define and examples
ligand with one lone pair
H2O, :NH3 , Cl-, OH-
Bidentate ligand - define and examples
ligands with two lone pairs, form two dative covalent bonds
Topic 15 - Transition metals 2
, 1,2- diaminoethane
Multidentate ligand - define and examples
more than two lone pairs
e.g. EDTA4- has six lone pair and forms 6 dative bonds with a metal ion
With relation to particles, what happens when [Cu(EDTA)]2- is formed from
[Cu(NH3)4]2+
the total number of particles on the right-hand side of the equation is greater
than on the left
Explain how the structure of haemoglobin uses ligands
its an iron(II) complex containing a multidentate ligand called a haem group
haem group is a ring made up of 4 nitrogen atoms that form 4 dative bonds to
the iron(II) ion
there are two other ligands bonded - a protein called globin and either oxygen
or water
Topic 15 - Transition metals 3
Transition metals
Define a transition metal
a transition metal is a d-block element which forms one or more stable ions
and incompletely filled d-orbitals
Describe the general physical and chemical properties of transition metals
physical - similar atomic radii, high densities and high melting and boiling points
chemical-
they form complexes
they form coloured ions in solution
variable oxidation states
good catalysts
Write the electronic configurations of Ar, Sc, Ti, Ni and V
Ar - 1s2 2s2 2p6 3s2 3p6
Sc - 1s2 2s2 2p6 3s2 3p6 4s2 3d1
Ti - [Ar] 4s2 3d2
Ni - [Ar] 4s2 3d8
V - [Ar] 4s2 3d3
Explain why Sc and Zn aren't transition metals
Scandium only forms one ion, Sc3+ which has an empty d sub-shell
Zinc only forms one ion Zn2+ which has a full d sub-shell
State and explain the electronic configuration of Chromium and copper
Chromium - [Ar]4s1 3d5
is it not [Ar]4s2 3d4 , because is it more stable if one of the 4s electrons is in the
3d orbital, so that each 3d orbital contains one unpaired electron
Topic 15 - Transition metals 1
, Copper - [Ar]4s1 3d10
it is not [Ar]4s2 3d9 , because it is more stable if the 3d subshell is completely
filled
State the formula of the ions and colour of the different oxidations of
vanadium
Complex ions
What are complex ions?
complex ions are metal ions surrounded by dative covalently bonded ligands
Define a ligand
ligand is an atom or ion or molecule that donates a pair of electrons to a central
mental atom/ion
a ligand must have at least one lone pair of electrons to form a dative covalent
bond with
Monodentate ligand - define and examples
ligand with one lone pair
H2O, :NH3 , Cl-, OH-
Bidentate ligand - define and examples
ligands with two lone pairs, form two dative covalent bonds
Topic 15 - Transition metals 2
, 1,2- diaminoethane
Multidentate ligand - define and examples
more than two lone pairs
e.g. EDTA4- has six lone pair and forms 6 dative bonds with a metal ion
With relation to particles, what happens when [Cu(EDTA)]2- is formed from
[Cu(NH3)4]2+
the total number of particles on the right-hand side of the equation is greater
than on the left
Explain how the structure of haemoglobin uses ligands
its an iron(II) complex containing a multidentate ligand called a haem group
haem group is a ring made up of 4 nitrogen atoms that form 4 dative bonds to
the iron(II) ion
there are two other ligands bonded - a protein called globin and either oxygen
or water
Topic 15 - Transition metals 3
