Periodic Table of elements – divided into s, p, d, f blocks

p block • p orbital partially fill

d block • d orbital partially filled • transition element

f block • f orbital partially fill

s block • s orbital partially fill

Periodic Table – s, p d, f block element s block elements • s orbitals partially fill

p block elements • p orbital partially fill

d block elements • d orbitals partially fill • transition elements

1 H 1s1

2 He 1s2

11 Na [Ne] 3s1

12 Mg [Ne] 3s2

5 B [He] 2s2 2p1

6 C [He] 2s2 2p2

7 N [He] 2s2 2p3

8 O [He] 2s2 2p4

9 F [He] 2s2 2p5

10 Ne [He] 2s2 2p6

13 Al [Ne] 3s2 3p1

14 Si [Ne] 3s2 3p2

15 P [Ne] 3s2 3p3

16 S [Ne] 3s2 3p4

17 CI [Ne] 3s2 3p5

18 Ar [Ne] 3s2 3p6

19 K [Ar] 4s1

20 Ca [Ar] 4s2

21 Sc [Ar] 4s2 3d1

22 Ti [Ar] 4s2 3d2

23 V [Ar] 4s2 3d3

24 Cr [Ar] 4s1 3d5

25 Mn [Ar] 4s2 3d5

26 Fe [Ar] 4s2 3d6

27 Co [Ar] 4s2 3d7

28 Ni [Ar] 4s2 3d8

29 Cu [Ar] 4s1 3d10

30 Zn [Ar] 4s2 3d10

n = 2 period 2

3 Li [He] 2s1

4 Be [He] 2s2

Click here video s,p,d,f blocks, Click here video on s,p,d,f notation Click here electron structure

Video on electron configuration

f block elements • f orbitals partially fill

Periodic Table – s, p d, f blocks element

Electron structure Chromium d block (Period 4)

1s2 2s2 2p6 3s2 3p6 4s1 3d5

[Ar] 4s1 3d5

Electron structure Germanium p block, Gp 14 (Period 4)

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p2

[Ar] 4s2 3d10 4p2

Electron structure Lead p block, Gp 14 (Period 6)

1s2 2s2 2p6 3s2 3p6 3d104s2 4p6 5s2 4d10 5p6 6s2 4f14 5d106p2

[Xe] 6s2 4f14 5d10 6p2

Electron structure Iodine p block, Gp 7 (Period 5)

1s2 2s2 2p6 3s2 3p6 3d104s2 4p6 5s2 4d10 5p5

[Kr] 5s2 4d10 5p5

Electron structure Cadmium d block (Period 5)

1s2 2s2 2p6 3s2 3p6 3d104s2 4p6 5s2 4d10

[Kr] 5s2 4d10

Electron structure Mercury d block (Period 6)

1s2 2s2 2p6 3s2 3p6 3d104s2 4p6 5s2 4d10 5p6 6s2 4f14 5d10

[Xe] 6s2 4f14 5d10

Gp 14 -4 valence electron Gp 17 - 7 valence electron

Gp 14 - 4 valence electron d block – d partially filled d block – d partially filled

d block – d partially filled

О

О

О

О

О

О

3d

Nuclear charge increase IE increase slowly

3d elec added to 3d sub level

3d elec – shield the outer 4s elec from nuclear charge

Ionization Energy – Transition metal Why IE increases slowly across ? IE Transition metal

Sc Ti V Cr Mn Fe Co

Period 4

Ni Cu

Shielding nuclear charge by 3d electron

+21 +22 +23 +24 +25 +26 +27 +28 +29

4s

Sc Ti V Cr Mn Fe Co Ni Cu Zn

+21 +22 +23 +24 +25 +26 +27 +28 +29 +30

Nuclear pull

Shielding by 3d electron Shielding by 3d electron

↓ Balance increase in nuclear charge

↓ Small increase in IE

↓ Easier to lose outer electron

↓ Variable oxidation state

Transition Metal (d block )

Across period

Cr - 4s13d5 • half filled more stable

Cu - 4s13d10 • fully filled more stable

Ca 4s2

K 4s1

Transition metal have partially fill 3d orbital • 3d and 4s electron can be lost easily • electron fill from 4s first then 3d • electron lost from 4s first then 3d • 3d and 4s energy level close together (similar in energy)

Filling electron- 4s level lower, fill first Losing electron- 4s higher, lose first

3d

4s

d block element with half/partially fill d orbital / sublevel in one or more of its oxidation states

Partially fill d orbital

Lose electron

↓

Formation ions

Sc3+

4s03d0 Zn 2+

4s03d10

Zn → Zn2+ 4s23d10 4s0 3d10

fully fill d orbital

Sc → Sc 3+ 4s23d1 4s0 3d0

empty d orbital

Transition Metal (d block )

NOT Transition element.

NOT Transition element.

О

О

Transition Metal

Physical properties Chemical properties

Element properties Atomic properties

• High electrical/thermal conductivity • High melting point • Malleable • Ductile • Ferromagnetic

• Ionization energy • Atomic size • Electronegativity

Transition Metal ( d block)

Gp 1 Gp 17

Sc

Ionization energy ↓

IE increase ↑ slowly ↓

Shielding of nuclear charge by 3d elec

↓ Electrostatic force

attraction ↓

Atomic size ↓

Decrease ↓ slowly ↓

Shielding of outer electron from

nuclear charge by 3d elec

Electronegativity ↓

EN increase ↑ slowly

Physical Properties

Zn

EN increase ↑

Atomic size decrease ↓

IE increase ↑

• Formation of complex ion • Formation coloured complexes

• Variable oxidation states • Catalytic activity

Formation complex ion Formation coloured complexes

Catalytic activity Variable Oxidation states

molecule adsorp on

surface catalyst

V Cr Mn Fe Co Ni

+2 +2 +2 +2 +2 +2

+3 +3 +3 +3 +3 +3

+4 +4 +4 +4 +4 +4

+5 +5 +5 +5 +5

+6 +6 +6

+7

Transition Metal – Variable Oxidation States

+3 +3 +3 +3 +3 +3

+2 +2 +2 +2 +2

+4 +4 +5

+2

+6 +6 +7

+2

+3

+4

+5

+6

+7

ScCI3 TiCI3 VCI3 CrCI3

MnCI3

FeCI3

CrCI2

MnCI2

FeCI2 CoCI2 NiCI2 CuCI2 ZnCI2

TiCI4

MnCI4 V2O5

Cr2O72-

+2

(VO2)2+

(MnO4)2-

(MnO4)-

oxides oxyanion

chlorides

+2 oxidation state more common +3 oxidation state more common

+3

CoCI3

Oxidation state Mn is highest +7

Highest oxidation state exist

↓

Element bond to oxygen

(oxide/oxyanion)

Oxidation state +2 common (Co → Zn)

↓

Harder to lose electron

↓

Nuclear charge (NC ↑) from Co - Zn

Oxidation state +3 common (Sc → Fe)

↓

Easier to lose electron

↓

Nuclear charge (NC ↓) from Sc - Fe

Transition metal – variable oxidation state

↓

4s and 3d orbital close in energy

↓

Easy to lose electron from 4s and 3d level

Ionic bond – more common for lower oxi states

TiCI2 – Ionic bond

Covalent bond – more common for higher oxi states

TiCI4 – Covalent bond

Highest oxidation states – bind to oxygen

Transition Metal

Formation coloured complexes Variable Oxidation states

Sc Ti V Cr Mn Fe Co Ni Cu Zn

+1

+2 +2 +2 +2 +2 +2 +2 +2 +2 +2

+3 +3 +3 +3 +3 +3 +3 +3

+4 +4 +4 +4 +4 +4 +4

+5 +5 +5 +5 +5

+6 +6 +6

+7

+3- most common

oxi state

+ 2- most common

oxi state

+ 7- Highest

oxi state

Click here vanadium ion complexes Click here nickel ion complexes

V5+/ VO2+ - yellow

V4+/ VO2+ - blue V3+ - green V2+ - violet

NiCI2 - Yellow NiSO4 - Green Ni(NO3)2

- Violet NiS - Black

Diff oxidation states

Colour formation

Nature of transition metal

Oxidation state

Diff ligands Shape Stereochemistry

Diff ligand Diff metals

MnCI2 - Pink MnSO4 - Red MnO2 - Black MnO4

- - Purple

Cr2O3 - Green CrO4

2- - Yellow

CrO3 - Red

Cr2O72-

- Orange

Shape/ Stereochemistry

Tetrahedral Octahedral

Blue Yellow

Transition Metal ion • High charged density metal ion • Partially fill 3d orbital • Attract to ligand • Form dative/co-ordinate bond (lone pair from ligand)

Ligand • Neutral/anion species that donate lone pair/non bonding electron pair to metal ion • Lewis base, lone pair donor – dative bond with metal ion

Ligand

+2

Formation complex ion

Transition Metal ion

Neutral ligand Anion ligand

H2O

NH3

CO

CI–

CN–

O2-

OH–

SCN–

: CI :

: .

Monodentate Bidentate

Polydentate

C2O42- C2H4(NH2)2

Drawing complex ion • Overall charged on complex ion • Metal ion in center (+ve charged) • Ligand attach • Dative bond from ligand

+3

4 water ligand attach 4 dative bond Coordination number = 4

6 water ligand attach 6 dative bond Coordination number = 6

Transition metal + ligand = Complex Ion

Coordination number

Shape Complex ion (metal + ligand)

Ligand (charged)

Metal ion (Oxidation #)

Overall charge on complex ion

linear [Cu(CI2)]- CI = -1 +1 - 1

[Ag(NH3)2]+ NH3 = 0 +1 + 1

[Ag(CN)2]- CN = -1 +1 - 1

Square planar

[Cu(CI)4]2- CI = -1 +2 - 2

[Cu(NH3)4]2+ NH3 = 0 +2 +2

[Co(CI)4]2- CI = -1 +2 - 2

Tetrahedral [Cu(CI)4]2- CI = -1 +2 - 2

[Zn(NH3)4]2+ NH3 = 0 +2 + 2

[Mn(CI)4]2- CI = -1 +2 - 2

Octahedral [ Cu(H2O)6]2+ H2O = 0 +2 + 2

[Fe(OH)3(H2O)3] OH = -1 H2O = 0

+3 o

[Fe(CN)6]3- CN = -1 +3 - 3

[Cr(NH3)4CI2]+ NH3 = 0 CI = -1

+3 + 1

Types of ligand: • Monodentate – 1 lone pair electron donor – H2O, F-, CI-, NH3, OH-, SCN- CN-

• Bidentate – 2 lone pair electron donor –1,2 diaminoethane H2NCH2CH2NH2, ethanedioate (C2O4)2-

•Polydentate – 6 lone pair electron donor – EDTA4- (ethylenediaminetetraacetic acid)

Complex ion with diff metal ion, ligand, oxidation state and overall charge

Mn+ L: :L

Mn+ :L

:L

L:

L:

Mn+

:L

:L

:L :L

Mn+

:L

:L

:L

:L

:L

:L

Coordination number – number of ligand around central ion

2

4

4

6

Ligand • Neutral/anion species that donate lone pair/non bonding electron pair to metal ion • Lewis base, lone pair donor – dative bond with metal ion

Neutral ligand Anion ligand

H2O

NH3

CO

CI–

CN–

O2-

OH–

SCN–

: CI : : .

Monodentate

Bidentate Polydentate

C2O42- C2H4(NH2)2

Ligand displacement

Co/CN > en > NH3 > SCN- > H2O > C2O42- > OH- > F- > CI- > Br- > I-

Spectrochemical series

Tetraaqua copper(II) ion

H2O displace by CI-

2+

CI- displace by NH3

Tetrachloro copper(II) ion

Stronger ligand displace weaker ligand

Tetraamine copper(II) ion

О

О

Stronger

ligand

Stronger

ligand

Chelating agent EDTA – for removal of Ca2+

• Prevent blood clotting • Detoxify by removing heavy metal poisoning

4s

3d

Magnetic properties of transition metals

Paired electron – spin cancel – NO net magnetic effect

Ti V Cr Mn Fe Co

Diamagnetism ↓

Paired electron ↓

No Net magnetic effect (Repel by magnetic field)

Ni Zn

Spin cancel

Sc

Spinning electron in atom – behave like tiny magnet

Unpaired electron – net spin – Magnetic effect

Spin cancel Net spin

Paramagnetism ↓

Unpaired electron ↓

Net magnetic effect (Attract by magnetic field)

Material

Diamagnetic Paramagnetic Ferromagnetic

• Iron • Cobalt • Nickel

Zn2+ Mn2+

Click here paramagnetism Click here paramagnetism Click here levitation bismuth Click here levitation

4s

3d

Magnetic properties of transition metal

Ti V Cr Mn Fe Co

Diamagnetism ↓

Paired electron ↓

No Net magnetic effect (Repel by magnetic field)

Zn

Spin cancel Net spin

Sc

pyrolytic graphite

Spin cancel Spin cancel

Paramagnetism ↓

Unpaired electron ↓

Net magnetic effect (Attract by magnetic field)

Diamagnetic Paramagnetic

Click here levitation bismuth Click here levitation

Click here paramagnetism measurement

Vs

Bismuth

Click here paramagnetism

Strong diamagnetic materials

Pt/Pd surface

Transition Metal – Catalytic Activity

Catalytic Properties of Transition metal • Variable oxidation state - lose and gain electron easily. • Use 3d and 4s electrons to form weak bond. • Act as Homogeneous or Heterogenous catalyst – lower activation energy • Homogeneous catalyst – catalyst and reactant in same phase/state • Heterogeneous catalyst – catalyst and reactant in diff phase/state • Heterogenous catalyst- Metal surface provide active site (lower Ea ) • Surface catalyst bring molecule together (close contact) -bond breaking/making easier

Transition metal as catalyst with diff oxidation states 2H2O2 + Fe2+ → 2H2O+O2+Fe3+

H2O2+Fe2+→H2O + O2 + Fe3+

Fe3+ + I - → Fe2+ + I2

Fe2+ ↔ Fe3+

Rxn slow if only I- is added H2O2 + I- → I2 + H2O + O2

Rxn speed up if Fe2+/Fe3+ added Fe2+ change to Fe3+ and is change back to Fe2+ again

recycle

molecule adsorp on

surface catalyst

Pt/Pd surface

Bond break

Bond making

3+

CH2 = CH2 + H2 → CH3 - CH3

Nickel catalyst

Without

catalyst, Ea

CH2= CH2 + H2 CH3 - CH3

Surface of catalyst for adsorption

With catalyst, Ea

adsorption H2

adsorption C2H4

bond breaking making

desorption C2H6

Fe2+ catalyst How catalyst work ?

Activation energy

• Haber Process – Production ammonia for fertiliser/ agriculture

3H2 + N2 → 2NH3

Uses of transition metal as catalyst in industrial process

Iron , Fe

Vanadium (V) oxide, V2O5

Nickel, Ni

Manganese (IV) oxide, MnO2

Platinum/Palladium, Pt/Pd Cobalt, Co3+

Iron , Fe2+ ion

Contact Process – Sulphuric acid/batteries 2SO2 + O2 → 2SO3

Hydrogenation Process- Margerine and trans fat

C2H4 + H2 → C2H6

Hydrogen peroxide decomposition – O2 production

2H2O2→ 2H2O + O2

Catalytic converter – Convertion to CO2 and N2

2CO + 2NO → 2CO2 + N2

Biological enzyme Hemoglobin – transport oxygen

Vitamin B12 – RBC production

NH3

Co3+

O2 Fe2+