The document discusses different allotropes of carbon including diamond, fullerene (C60), graphene, and graphite. It provides details on their molecular structures, bonding, and properties. Diamond has a giant covalent structure and is the hardest known material. Fullerene has 60 carbon atoms arranged in a hollow spherical shape. Graphene is a single layer of sp2 hybridized carbon atoms arranged in a hexagonal honeycomb lattice. Graphite consists of layers of graphene held together by weak van der Waals forces between the layers. It is a good lubricant and widely used in pencils and electrodes.

1. Allotropes of Carbon
Element exist in different form/physical state
Diamond
Fullerene, C60
•Carbon-sp2hybridization
•Bonded in geodesic shape
•60 carbon in spherical -20 hexagon/ 12 pentagon
•1 πelectron free to delocalized.
•Surface is not planar, but sphere
•Electrons NOTable to flow easily.
Graphene
•Carbon-sp2hybridization
•Carbon bond to 3 others form hexagon (120)
•Exist chicken wire/honeycomb-1 layer
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•Carbon-sp3hybridization
•Bonded tetrahedrally
•Strong hard covalent network
•Carbon-sp2hybridization
•Bonded Trigonalplanar (layers)
•Giant covalent structure (2D)
•Strong covalent network within layers
•Weak Van Der Waals force bet layers
Giant covalent structure (3D)
Giant covalent structure (2D)
Molecular structure
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Giant covalent structure (2D)
✓
Uses of graphene
Graphite
Bond to 4 C atoms
Bond to 3 C atoms
Bond to 3 C atoms
…

2. Allotropes of Carbon
Element exist in different form/physical state
Diamond
Fullerene, C60
Graphene
Graphite
Electrical conductivity
Special property
Electrical conductivity
Electrical conductivity
Electrical conductivity
Special property
Good
-Within layer, C sp2hybridized
-ONEfree delocalized πelectron
Very Good
-Within layer, C sp2hybridized
-ONEfree delocalizedπelectron
moving across the layer easily
Poor
-C sp3hybridized
-No free moving electron
Semiconductor
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✗
-Surface sphere, notplanar
-Electrons CANNOTflow easily.
-Lower electron mobility
-Soft, layer slide
across each other
-Hardest substance
-Jewellery
Special property
graphite
lubricant
electrode
Lightest/strongest material
replacing silicon in photovoltaic cell
Drug delivery
Transistor/Electronic
Transparent conducting
electrode
Clickhereuses graphene
Drug in graphene

3. Allotropes of Carbon
Element exist in different form/physical state
Fullerene, C60
Graphene
Click hereto view touch screen
Electron in hexagonal rings do not
delocalized over whole molecule.
6:6 bond shorter than 6:5
6:5 bond bet hexagon and pentagon
Macroscopic properties
•High tensile strength
•Highelectrical /heat conductivity
•High ductility andchemical inactivity
60 carbon in spherical
((20 hexagon/12 pentagon)
Potential medicinal use
•Trap/bind drug inside/outside cage
•Target cancer cells
Drug inside
Drug bind outside
•sp2hybridization
•Exist as 2D/chicken wire/honeycomb
•Stronger than diamond, x200 stronger steel
•Conductive than copper
•Flexible/Transparent/lighter than rubber
•Solar cell and batteries
Graphenetouch screen and photovoltaic cell
Click herefor application of graphene
Single sheet conductor
Rool into conductive nanotubes
Electrical contact
photovoltaic cell
Lightest and strongest replacing silicon in photovoltaic cell
6:6 bond length bet two hexagon
Double bond
Single bond

4. Uses of Carbon Allotropes
•Conduct current/heat very well
•Conduct current at speed of light
•Electron delocalized above/below plane
•High electron mobility
Click herediscovery graphene
Click hereCNT
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sp2hybridization
graphene
rool into
rool into
Carbon Nanotube (CNT)
CNT-fullerene family of carbon allotropes.
Hollow cylindrical molecule
Rolling single or multiple layers of graphenesheet.
Single-wall SWNT/ multi-wall MWCNT
High tensile, stable, unreactive
Single wall Nanotube (SWNT)
Multi wall Nanotubes (MWNT)
Click hereTEDtalk graphene
1 layer thick
Uses of CNT
Strong tubes as
space elevator
Filter off salt
(desalination)
Drug delivery to body
Attachment drug
therapeutics

5. Metallic Bonding
Metals
Metallic bonding
Electrostatic forces attraction
-bet lattice of positive ions with
delocalized electron
Metallic elements-Cu, Na, K, Cu
Lattice of positive ions with sea of free electrons
Metallic Bonding
Metallic Property
Electrical conductivity
Malleability/Ductile
High melting point
Delocalized free moving electron carry charge/heat
heat flow
High Temp
Low Temp
Thermal conductivity
electron flow
✓
Form sheet by hammering
Ductile -stretch into wires
Bend and shaped
Atom able to roll/slide to new position
without breaking metallic bond
Strong Electrostatic force attraction
-between lattice of positive ions with
delocalized electron

6. Melting Point
•Temp when solid turn to liquid (temp remain constant)
•Energy absorb to overcome forces attraction bet molecule
Factors affecting melting point for metals
•Melting point across Period 2/3
•Melting point down Gp1
Gp 1
Period 2/3
Metallic Bonding
Melting Point metals
period 2
period 3
Li
Be
B
C
N O F Ne
Na
Mg
AI
Si
P S
CI
Melting point across Period 2 and 3
Electrostatic forces attraction
-bet lattice of positive ions with
delocalized electron
Melting point across
Period 2 and 3
Size of atom decrease ↓
Number delocalized
electron increase ↑
Electrostatic forces attraction
INCREASES ↑
Melting point
INCREASE ↑
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Electrostatic force attraction
Metallic Bonding
Metalic Bonding
INCREASE ↑

7. Melting Point
Factors affecting melting point for metals
Gp 1
Period 2/3
Metallic Bonding
Melting Point metals
Melting point down Group 1
Electrostatic forces attraction
-bet lattice of positive ions with
delocalized electron
Melting point
down Gp1
Size of atom increase ↑
Valence electron further
away from positive nucleus
Electrostatic forces attraction
DECREASES ↓
Melting point
DECREASE ↓
✓
Electrostatic force attraction
Metallic Bonding
Size of atom increases
Metallic Bonding
DECREASE ↓
•Temp when solid turn to liquid (temp remain constant)
•Energy absorb to overcome forces attraction bet molecule
•Melting point across Period 2/3
•Melting point down Gp1

8. Melting Point
Gp 1
Period 2/3
Metallic Bonding
Melting Point metals
Electrostatic forces attraction
-bet lattice of positive ions with
delocalized electron
✓
Electrostatic force attraction
Metallic Bonding
Number delocalized electrons
Factors affecting Metallic Bonding
Charge on cation
Radius cation
Higher ↑ charge cation
Higher ↑metallic bonding
(melting point)
Bigger ↑ radius cation
Lower ↓ metallic bonding
(melting point)
Higher ↑ number delocalized electrons
Why m/p Na (Gp1) less than Mg (Gp2) ?
Why melting point different?
ONE delocalized
electron per atom
TWO delocalized
electron per atom
Radius cation Bigger ↑
Radius cation Smaller ↓
MELTING POINT
MELTING POINT
Higher ↑metallic bonding
(melting point)
Charge cation smaller ↓
Charge cation Bigger ↑
•Temp when solid turn to liquid (temp remain constant)
•Energy absorb to overcome forces attraction bet molecule
•Melting point across Period 2/3
•Melting point down Gp1
+1
+2

9. Heating mixture metals together
Alloy cool/solidifies, mechanical property diff from its individual constituents
Metals/non-metals often enhance its properties.
Induce strength/hardness by occupying empty spaces bet lattice structure
Metals
•Same type of elements/atom arrangement
•Malleable –shaped by hammering
•Ductile –deform/ turn to wire
Aluminium
-Soft/malleable
structure-crystalline lattice same type atoms
Click herefor list of alloys
Metals VsAlloy
Alloy
•Mixture metals / non metal
•Property alloy far superior than its element/metal
•Stronger, harder and enhanced qualities than metals
structure-crystalline lattice different atomic sizes
Duralumin (Aluminium+ Copper)
Strong aircraft
Metals
Alloy
Vs
Vs
Iron
-Soft/malleable
Steel
-Strong/Hard
What makes alloy strong?
Metal occupy spaces
in between
Heat mixture metals
Malleable (hammer)
Ductile (Stretch)
Mixture of metals
in lattice
Strong + hard
✓
✓
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✗
Click hereuses alloy -nitinolrobot

10. Metals
Structure-crystalline lattice same type atoms
Metals VsAlloy
Property alloy far superior
than its element/metal
Structure-crystalline lattice different atomic sizes
Vs
Malleable (hammer)
Ductile (Stretch)
Mixture of metals
in lattice
Alloy
Component
Property/Uses
Steel
Iron+ Carbon
Structural material
Stainless steel
Iron+ Carbon +Nickel +Chromium
Corrosion resistance
Brass
Copper+ Zinc
Decorative
Bronze
Copper+ Tin
Coins and medals
Duralumin
Aluminium+ Copper + Manganese
Aircraft
Nichrome
Nickel+ Chromium
Heating element
Pewter
Tin+ Copper + Antimony
Decorative
Nitinol
Nickel+ Titanium
Shape memory, actuator
Bold –Base main metal used
Same type atom
arrangement
Ductile –
Deform/turn to wire
Malleable –
Shaped by hammer
Alloy
Mixture metals/non metal
Stronger, harder-enhance qualities than metals
+
✓
Metal + Metal = Alloy
Click heredifferent alloys
Types of Alloy
Steel
Stainless steel
Brass
Bronze
Duralumin
Nichrome
Pewter
Click hereuses alloy -nitinol robot
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11. Crystalline Structure
Giant metallic
Giant Ionic
Giant Covalent Network
Simple Molecular
Non Polar Polarmolecule H2Bonding
Particles
Atoms(Metals)
Na, K, Li, Ca, Mg
Ion (+ve/-ve ions)
Na+CI-, K+CI-
Atoms from Gp4 (Carbon/Silicon)
Molecules with Molecule with Molecule with H atom -Similar EN value -Different EN value -bonded to N, O, F
-Bond polarity cancel –Dipole moment (electronegative atom) -Symmetrical -Asymmetrical
Bonding
Lattice of positive ions with sea of electrons
Electrostatic forces attraction bet +ion with electron
Lattice of positive and negative ions
Electrostatic forces attraction bet +ion with -ion
Giant covalent throughout 3D
structure.
Within molecule Within molecule Within molecule
-strong covalent -strong covalent -strong covalent
Between molecule Between molecule Between molecule
-weak intermolecular -weak intermolecular -weak intermolecular
-VDF -VDF -VDF
-Dipole-dipole -Dipole -dipole
-H2bonding
Physical
Property
State
Solid
(Non volatile)
Solid
(Non volatile)
Solid
(Non volatile)
Liq/Gas Liq/Gas Liq/Gas
(Volatile) (Volatile) (Volatile)
Melting
Point
HIGH
HIGH
VERY HIGH
Very Low Very Low Very Low
Conduct
Good Conductor
-free moving
electron
Good conductor
-free moving ions in
molten/aqstate
Poor conductor
-Diamond, SiO2
Semiconductor
-Graphite, C60
Good conductor
-Graphene
Poor conductor Poor conductor Poor conductor
Solubility
Insoluble
Soluble in polar
solvent
Insoluble
Soluble in polar Soluble in non polar Soluble in polar solvent
solvent solvent
Sea electrons
+ve / -ve ions
Strong Covalent
Metallic Bonding
Ionic Bonding
✓
CI
CI
CI
CI
CI
CI
....
Between
molecule
Within
molecule
....
Between
molecule
Within
molecule
H2 Bonding
Carbon atoms
Silicon atoms