Download Transition metal

A2 CHEMISTRY UNIT 5- PIGUY
T R A N S I T I O N M E TA L S
>>REVISION>>
TRANSITION
M E TA L S
• Transition metal - d-block
element which forms one
or more stable ions with
partially filled 3d sub-shell.
ELECTRON
C O N F I G U R AT I O N S
Fe 2+
3d
4s
[Ar]
T R A N S I T I O N M E TA L
- show variable oxidation
number in compounds
- form coloured solutions
- form complex ions
- act as catalysts, both as
elements and as
compounds
Zn 2+
3d
[Ar]
N O T A T R A N S I T I O N M E TA L
4s
COLOURED
IONS
• ligands around ions cause 3d-
orbital to split into two levels
SPLITTING THE
D - O R B I TA L
3d
[Ar]
• transition of electrons between
the levels occurs
• when electron is promoted to a
higher level, energy is absorbed
• a specific frequency of light is
associated with this energy
• frequencies not absorbed
appears
blue & green
not absorbed
4s
T H E N O TAT I O N U S E D L AT E R …
Y
X
X
X
X
colour (co-ordination number)
acid-base reaction
ligand exchange
redox
Y
Y
Y
precipitates have co-ordination numbers such that they are uncharged.
acid-base reaction with NH3 also produces NH4+; CO2 with CO32-.
SUMMARY OF COLOURS
dilute
excess
NaOH (aq) or NH 3 (aq)
Chromium (III)
Nickel (II)
green ppt.
NaOH
green soln. (6) purple soln. (6)
green ppt.
blue soln. (4)
Iron (II)
green ppt. (later brown)
Iron (III)
brown ppt.
Copper (II)
Zinc (II)
deep blue
soln. (4)
blue ppt.
Manganese (II)
NH 3 (aq)
off-white ppt.
white ppt.
colourless soln. (4)
COPPER (II) REACTIONS
YELLOW
YELLOW
[CuCl4]2-
CuCO3 (s)
H2O
CO32-
BLUE
[Cu(H2O)6]2+
OH-
BLUE
H+
Cu(H2O)4(OH)2 (s)
conc.
NH3
R O YA L
BLUE
[Cu(H2O)2(NH3)4]2+
HCl
CHROMIUM (III) REACTIONS
YELLOW
CrO4
H+
ORANGE
Cr2O72GREEN
2-
OH- / H2O2
GREEN
OH-
[Cr(OH)6]3-(aq)
conc.
NaOH
H+ / Zn
OH- / CO32-
[Cr(H2O)6]3+(aq)
Cr(H2O)3(OH)3 (s)
H+
conc.
NH3
H+ / Zn
2+
[Cr(H2O)6] (aq)
BLUE
GREEN
PURPLE
[Cr(NH3)6]3+(aq)
IRON (II) REACTIONS
Fe(H2O)3(OH)3 (s)
BROWN
O2 / H2O
Fe(H2O)4(OH)2 (s)
OH-
GREEN
H+
2+
[Fe(H2O)6] (aq)
GREEN
CO32-
FeCO3 (s)
GREEN
IRON (III) REACTIONS
Fe(H2O)3(OH)3 (s)
OH- / CO32-
BROWN
H+
3+
[Fe(H2O)6] (aq)
YELLOW
SUMMARY OF SHAPES
OCTAHEDRAL
TETRAHEDRAL
SQUARE PLANAR
LINEAR
co-ordination
number
6
4
4
2
bond
angle
90
109.5
90
180
often with Cl -
Pt 2+ and Ni 2+
complexes
Ag +
complexes
occurs
most complexes
Cl-
H2O
H2O
shape
OH2
Cr 3+
H2O
H2O
OH2
ClCl-
Cu 2+
Cl-
NH3
Pt 2+
Cl-
Cl-
NH3
Ag +
NH3
NH3
YOU’RE
DONE WITH
INORGANIC
CHEMISTRY
REVISION!