3.2.5 Transition Metals Flashcards
Which block are transition metals found in?
d-block
What is a transition metal?
A metal that can form one or more stable ions with a partially filled d sub-level
(d-orbital can contain up to 10 electrons)
State which period 4 d-block elements are transition metals
All period 4 d-block elements are transition metals expect scandium and zinc
What causes transition metals to have special chemical properties?
Incomplete d sub-level
Explain why scandium isn’t a transition metal
- Scandium only forms one ion, Sc3+, which has empty d sub-level
- Sc = [Ar] 3d1 4s2
- When loses 3 electrons to form Sc3+
- Ends up with electron configuration [Ar]
Explain why zinc isn’t a transition metal
- Zinc only forms one ion, Zn2+, which has full d sub-level
- Zn = [Ar] 3d10 4s2
- Forms Zn2+ = loses 2 electrons both from 4s sub-level
- ∴ keeps full 3d sub-level
Transition metals form ______ ions
positive
s electrons removed first & then d electrons


Name 4 special chemical properties of transition metals
- Form complex ions
- Form coloured ions
- Good catalysts
- Exists in variable oxidation states
Why do elements show variable oxidation states?
- ∵ energy levels of 4s and 3d sub-levels are very close to one another
- ∴ different no. of electrons can be gained or lost using fairly similar amounts of energy
Oxidation state +7
State colour of MnO4-
Purple
Oxidation state +6
State colour of Cr2O72-
orange
Oxidation state +5
State colour of VO2+
yellow
Oxidation state +4
State colour of VO2+
blue
Oxidation state +3
State colour of V3+
green
Oxidation state +3
State colour of Cr3+
violet/green

Oxidation state +3
State colour of Fe3+
purple/yellow

Oxidation state +2
State colour of V2+
Violet
Oxidation state +2
State colour of Mn2+
Pale pink
Oxidation state +2
State colour of Fe2+
Pale green
Oxidation state +2
State colour of Co2+
Pink
Oxidation state +2
State colour of Ni2+
green
Oxidation state +2
State colour of Cu2+
blue
Define a complex
A complex is a central metal atom or ion surrounded by co-ordinately bonded ligands









































































