topic 15: transition metals Flashcards
what is the electronic configuration of Sc
1s2 2s2 2p6 3s2 3p6 4s2 3d1
what is the electronic configuration of Ti
1s2 2s2 2p6 3s2 3p6 4s2 3d2
what is the electronic configuration of V
1s2 2s2 2p6 3s2 3p6 4s2 3d3
what is the electronic configuration of Cr
1s2 2s2 2p6 3s2 3p6 4s1 3d5
what is the electronic configuration of Mn
1s2 2s2 2p6 3s2 3p6 4s2 3d5
what is the electronic configuration of Fe
1s2 2s2 2p6 3s2 3p6 4s2 3d6
what is the electronic configuration of Co
1s2 2s2 2p6 3s2 3p6 4s2 3d7
what is the electronic configuration of Ni
1s2 2s2 2p6 3s2 3p6 4s2 3d8
what is the electronic configuration of Cu
1s2 2s2 2p6 3s2 3p6 4s1 3d10
what is the electronic configuration of Zn
1s2 2s2 2p6 3s2 3p6 4s2 3d10
what is a transition metal
d-block elements that form one or more stable ions with incompletely-filled d-orbital
what are the characteristics of transition metals
- complex formation * formation of coloured ions
- variable oxidation state
- catalytic activity
why is Zn not a transition metal
Zn can only form a +2 ion. in this ion the Zn2+ has a complete d orbital and so does
not meet the criteria of having an incomplete d orbital in one of its compounds
why is Sc not a transition metal
Sc can only form a +3 ion. In this ion the Sc3+ has an empty d orbital and so does not meet the criteria of having an incomplete d orbital in one of its ions
what is a complex
s a central metal ion surrounded by ligands
what is a ligand
an atom, ion or molecule which can donate a lone electron pair
coordinate bonding
co-ordinate bonding is involved in complex formation. co-ordinate bonding is when the shared pair of electrons in the covalent bond
come from only one of the bonding atoms. co-ordination number: the number of co-ordinate bonds formed to a central
metal ion
ligands can be monodentate, bidentate or multidentate. what do these words mean
can form one coordinate bond per ligand
which have two atoms with lone pairs
and can form two coordinate bonds per ligand
describe the structure of EDTA4- anion
6 donor sites (4O and 2N) and forms a 1:1
complex with metal(II) ions
colour changes arise from changes in what 3 things
oxidation state
co-ordination number
ligand
[Co(NH3)6]2+ (aq) [Co(NH3)6]3+ (aq) +e- yellow —> brown
what causes the colour change in the equation
in this equation only oxidation state is changing
Cu(H2O)62+ + 4Cl- [CuCl4]2- + 6H2O
blue —> green
what causes the colour change in this equation
In this equation both ligand and co- ordination number are changing
Co(H2O)62+ + 6 NH3 Co(NH3)62+ + 6H2O
pink —> yellow brown
in this equation only the ligand is changing
how do colour arises
colour arises from electronic transitions from the ground state to excited states: between different d orbitals
a portion of visible light is absorbed to promote d electrons to higher energy levels. the light that is not absorbed is transmitted to give the substance colour