Decoding the Tweet _ Practical Criticism in the Age of Hashtag.pptx
IB Chemistry on Valence Bond and Hybridization Theory
1. Tutorial on Valence Bond Theory and
Hybridization.
Prepared by
Lawrence Kok
http://lawrencekok.blogspot.com
2. brown liquid
. :
: :
x
x
Click here simulation on covalent bond
yellow gas
greenish gas
violet solid
Covalent Bonding
Covalent bonding between non metals
2.8.7
Gp 17 Non metal
achieve stable octet structure
Covalent Bonding
Electrostatic forces attraction between
nucleus with shared pair electron
CI shared pair electron
2.8.8
2.8.7
Sharing
electron
Gp 17 Non metal
2.8.8
CI
Non metal
•High EN value
•Gain electron (anion)
•Electronegative ions
CI CI
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
: :
CI CI : xx
x
x
X
x
x
xx
CI CI
x
x
CI CI
Non metal
•High EN value
•Gain electron (anion)
•Electronegative ions
Single covalent bond – shared pair electron
3. Bond Bond
:
. C
I.
B - 6 valence e : :
.
x
order
Bond
strength
Bond
length/pm
C - C 1 347 154
C = C 2 612 134
C Ξ C 3 820 120
N - N 1 159 145
N = N 2 418 123
N Ξ N 3 914 110
Bond length and Bond strength
Bond length = 0.199nm
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
: :
x
x
: :
: CI CI xx
. Electron cross dot
. Valence/bonding pair electron
. Electron cross dot
. Valence/bonding pair electron
. :
: :N N: N N
:
.
x
x
X
X
xx
CI CI
Lewis structure/diagram
O
x
x
x
x
xx
CI CI
:O : xx
O
:
x
x
x
x
x
O
:
:
x
x
x
N
O O
Lewis structure/diagram
: N
O
:
Triple bond > Double bond > Single bond
Bonding pair e
-involve in bonding
Bond length decrease
Bond strength Increase
(Double/Triple bond)
Bond length = 0.121nm
Bond length = 0.110nm
Bond order up – Bond strength up – Bond length down
: O
Non bonding pair
(Lone pair electron)
Bonding
pair electron
Dative bond
(electron pair of oxy)
:C O:
Bonding pair electron
Types of bonding
Lone pair e
–not involve in bonding
Dative/coordinate bond
- pair e come from an atom
Exception to octet rule
All period 2 element
- observe octet rule
except Be and B
Electron deficient
Less than 8 valence e
All period 3 element
- observe octet rule
except P and S
Expanded octet
More than 8 valence e
: :
: :
:CI .x Be CI:
x
x.
Be - 4 valence e
:
: x :
: :
CI B CI
:
CI
P S
CI
CI
CI
CI
CI
CI CI
CI CI
CI
P - 10 valence e
S – 12 valence e
:
:
4. Valence Shell Electron Pair Repulsion
Predict molecular shape/geometry Shape determine by electron pairs/
electron charge centers/ECC
Bonding/lone pair – repel each other
Bonding/lone pair arrange themselves as far as possible
(minimise repulsion)
Valence
Shell
Electron
Pair
Repulsion
NOT surrounding atoms
..
N
H
H H
Principles of VSEPR
Shape of molecule
1 Determine number valence e around central atom
2 Single, double, triple bond , lone pair act as electron
charge center/ECC
3
4 Lone pair-lone pair > Lone pair-bonding pair > bonding
pair-bonding pair repulsion
5
6 ECC or electron pair position in equatorial first, then axial
Lewis structure
..
N
H
H
VSEPR
H
Shape
Excellent VSEPR simulation Click here ✓ Click here VSEPR simulation
Click here VSEPR notes
5. 1 lone pair 4 ECC N – central atom
..
Valence Shell Electron Pair Repulsion
Principles of VSEPR
Determine number 1 valence e around central atom
2 Single, double, triple bond , lone pair act as
electron charge center/ECC
3 Bonding/lone pair repel each other
Lone /lone pair > Lone /bond pair > bond/bond pair repulsion
Bonding/lone pair arrange themselves as far as possible
(minimise repulsion)
4
5
For 5/6 ECC:
ECC position in equatorial first, then axial
..
N
H H H
3 bonding pair
C
H H C N
3 ECC
H
=O
2 ECC
H O H
..
4 ECC
2 lone pair 1 lone pair 0 lone pair
> >
Repulsion
greater
Repulsion
greater
Repulsion greater - Bond angle smaller
✓
ECC far apart – Bond angle greatest – minimise repulsion
6
Lone pair need more space
Multiple bonds more space
Equal repulsion Unequal repulsion
90°
120°
109.5°
107°
180°
6. Valence Shell Electron Pair Repulsion
Predict molecular shape/geometry Shape determine by electron pairs/
electron charge centers/ECC
Bonding/lone pair – repel each other
Bonding/lone pair arrange themselves as far as possible
(minimise repulsion)
Valence
Shell
Electron
Pair
Repulsion
..
N
H
H H
Principles of VSEPR
Shape of molecule
1 Determine number valence e around central atom
2 Single, double, triple bond , lone pair act as electron
charge center/ECC
3
4 Lone pair-lone pair > Lone pair-bonding pair > bonding
pair-bonding pair repulsion
5
6 ECC or electron pair position in equatorial first, then axial
Lewis structure
..
N
H H H
VSEPR
Geometry
4 ECC
3 bonding pair
1 lone pair
Trigonal pyrimidal
1
2
3
Bond pair electron
•Occupy smaller region
space bet nuclei
•Repulsion less
Lone pair electron
nucleus
>
Bonding pair electron
nuclei
Lone pair electron
•Electron pair occupy
greater space
•Repel any bonding pair nearby
•Lone pair repulsion > bonding pair repulsion
Double bond
•Repulsion greater
•Angle smaller, 111.4°
B
F
120°
F
F
120°
120°
Single bond
•Equal repulsion
•Angle 120°
space occupy
by electron
space occupy
by electron
7. Valence
Shell
Electron
Pair
Repulsion
..
N
H
H H
Shape of molecule
- Lewis structure
- Valence electron involve in bonding
- Localized region space
- Sharing of valence electron
..
N
H
H H
Geometry
4 ECC
3 bonding pair
1 lone pair
Trigonal pyrimidal
1 2 3
Using VSEPR
predict shape
- Atomic orbital overlap
- Electron localized in overlap region
-Electron density between nuclei
Quantum mechanics approach
1s orbital 1s orbital
1s orbital 2p orbital
2p orbital 2p orbital
Localized
electron pair
1s 1s
Electron density/cloud
Too near repulsion
bet +ve nuclei
Attraction bet nuclei
with electron cloud
Minimum energy, most stable, bond length
8. Atomic Orbitals
n= 2
n= 1
l=2
l=1
l=0
3d sublevel
3p sublevel
2p sublevel
2s sublevel
l=0 1s sublevel
n= 3
l=1
l=0 3s sublevel
ml =+2
ml =+1
ml = 0
ml =-1
ml =-2
ml =+1
ml = 0
ml =-1
ml = 0
ml =+1
ml = 0
ml =-1
ml =0
ml =0
3dx
2 – y
3dyz orbital
3dz
2 orbital
3dxz orbital
3dxy orbital
3py orbital
3pz orbital
3px orbital
3s orbital
2py orbital
2pz orbital
2px orbital
2s orbital
1s orbital
2orbital
Click here to view simulation
Energy Level
Atomic orbital overlap
Electron localized in overlap region
Electron density bet nuclei
1s orbital 1s orbital
1s orbital 2p orbital
2p orbital 2p orbital Localized
electron pair
Click here hybridization notes
Click here orbital overlap
9. Sigma σ bond
•2 atomic orbital overlap
•End to end overlap along internuclear axis
•Overlap of orbitals between nuclei
•Constructive interference
overlap
Molecular orbital
sigma bond
Pi π bond
•2 p orbital overlap sideways
•Overlap of unhybridized/parallel p orbital
•Parallel p orbital overlaps
•Sideway interaction of 2 p orbitals
+
Atomic orbital overlap
+
overlap
Atomic orbital overlap
+ +
Molecular orbital
pi bond
10. Sigma σ bond
•2 atomic orbital overlap
•End to end overlap along internuclear axis
•Overlap of orbitals between nuclei
•Constructive interference
sigma bond
overlap
Molecular orbital
sigma bond
Pi π bond
•2 p orbital overlap sideways
•Overlap of unhybridized/parallel p orbital
•Parallel p orbital overlaps
•Sideway interaction of 2 p orbitals
+
Atomic orbital overlap
+
overlap
internuclear axis
Atomic orbital overlap
+ +
Molecular orbital
pi bond
+
Sigma bond stronger- greater orbital overlap Pi bond weaker - less orbital overlap
12. Mixing of atomic orbital to form new hybrid orbital for bonding
Atomic orbital + Atomic orbital → Hybrid orbital
One s orbital + One p orbital TWO → sp hybrid orbital
+
50% s character
50% p character
One s orbital + Two p orbital → THREE sp2 hybrid orbital
+ +
33% s character
66% p character
One s orbital + Three p orbital → FOUR sp3 hybrid orbital
+ + +
Formula
Lewis Structure
VSEPR
Hybridization
NH3
1
2
3
4
H
H
H
1
2
3
4
25% s character
75% p character
13. Mixing of atomic orbital to form new hybrid orbital for bonding
Atomic orbital + Atomic orbital → Hybrid orbital
One s orbital + One p orbital TWO → sp hybrid orbital
+
50% s character
50% p character
One s orbital + Two p orbital → THREE sp2 hybrid orbital
+ +
33% s character
66% p character
One s orbital + Three p orbital → FOUR sp3 hybrid orbital
+ + +
Formula
Lewis Structure
VSEPR
Hybridization
NH3
1
2
3
4
H
H
H
VSEPR
Electron Domain
Electron charge center
Hybridization
2 sp
3 sp2
4 sp3
5 dsp3
6 d2sp3
1
2
3
4
Atomic
orbital
Type of
Hybridization
Number
Hybrid
orbitals
VSEPR
Number
Electron
domain
VSEPR
Electron
geometry
domain
s,p sp 2 2 Linear
s,p,p sp2 3 3 Trigonal
planar
s,p,p,p sp3 4 4 Tetrahedral
s,p,p,p,d dsp3 5 5 Trigonal
Bipyrimidal
s,p,p,p,d,d d2sp3 6 6 Octahedral
25% s character
75% p character
Excellent simulation✓
Click here for simulation
14. Valence
Shell
Electron
Pair
Repulsion
..
N
H
H H
Shape of molecule
..
N
H
H H
Geometry
4 ECC
3 bonding pair
1 lone pair
Trigonal pyrimidal
1 2 3
- Lewis structure
- Valence electron involve in bonding
- Localized region space
- Sharing of valence electron
Using VSEPR
predict shape
15. Valence
Shell
Electron
Pair
Repulsion
..
N
H
H H
Shape of molecule
- Lewis structure
- Valence electron involve in bonding
- Localized region space
- Sharing of valence electron
..
N
H
H H
Geometry
4 ECC
3 bonding pair
1 lone pair
Trigonal pyrimidal
1 2 3
- Atomic orbital overlap
- Electron localized in overlap region
-Electron density between nuclei
Using VSEPR
predict shape
- Quantum mechanics approach
- Strength covalent bond proportional to overlap bet orbitals
- Greater overlap – stronger bond
- Atom undergo hybridization to maximize overlap
- Wave combine constructive/destructively form hybrid orbital
1s orbital 1s orbital
1s orbital 2p orbital
2p orbital 2p orbital
Localized
electron pair
Orbital
- Probability of finding electron in a region space
- Cloud of probability
- Not possible determine exact location electron
- Electron density
Electron cloud
16. sp hybridization, Beryllium hydride, BeH2
sp sp
1s
1s
2s
s orbital p orbital
2p
4Be - 1s2 2s2
1s
2p
High energy
excited
Ground state Excited state
2py 2pz
Hybridized state
2s
sp
hybridization
+
sp hybrid orbital
+ +
Be
H – Be - H
Be – sp hybridization
- TWO sp hybrid orbitals
- Linear electron distribution
- 2 bonding pair
- sp orbital Be overlap
with s orbital hydrogen
17. sp hybridization, Beryllium hydride, BeH2
sp sp
1s
1s
2s
s orbital p orbital
2p
4Be - 1s2 2s2
1s
2p
High energy
excited
Ground state Excited state
2py 2pz
Hybridized state
2s
sp
hybridization
+
sp hybrid orbital
+ +
Be
H – Be - H
sp2 hybridization Boron hydride, BH3
High energy
2s
1s
5B - 1s2 2s3
Ground state
2p
+ +
1s
2s
2p
1s
2p
excited
sp2
hybridization
sp2 sp2 sp2
B
Excited state Hybridized state
Be – sp hybridization
B
- TWO sp hybrid orbitals
- Linear electron distribution
- 2 bonding pair
- sp orbital Be overlap
with s orbital hydrogen
H
B – sp2 hybridization
- THREE sp2 hybrid orbitals
- Trigonal electron distribution
- 3 bonding pair
- sp2 orbital B overlap
with s orbital hydrogen
B
H H
18. sp3 hybridization methane, CH4
1s
1s
2s
2p
6C - 1s2 2s22p2
1s
2p
excited
Ground state Excited state
Hybridized state
2s
sp3
hybridization
+
sp3 sp3 sp3 sp3
C +
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 4 bonding pair
- sp3 orbital carbon overlap
with s orbital hydrogen
CH4
19. sp3 hybridization methane, CH4
sp3 sp3 sp3 sp3
1s
1s
2s
2p
6C - 1s2 2s22p2
1s
2p
excited
Ground state Excited state
Hybridized state
2s
sp3
hybridization
+
sp3 hybridization ammonia NH3
2s
1s
Ground state
2p
1s
2s
2p
1s
excited
+
sp3
hybridization
sp3 sp3 sp3
Excited state Hybridized state
C +
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 4 bonding pair
- sp3 orbital carbon overlap
with s orbital hydrogen
7N - 1s2 2s22p3
sp3
+
NH3
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 3 Bonding pair/1 lone pair
- sp3 orbital nitrogen overlap
with s orbital hydrogen
CH4
20. sp2 hybridization ethene, C2H4
1s
1s
2s
2p
6C - 1s2 2s22p4
1s
2p
excited
Ground state Excited state
Hybridized state
2s
sp2
hybridization
+
sp2 sp2 sp2
unhybridized
2p orbital
C2H4
unhybridized 2p orbital
overlap form π bond
C
21. sp2 hybridization ethene, C2H4
2p
excited
2s
1s
2p
1s
1s
2s
2p
6C - 1s2 2s22p4
1s
2p
Ground state Excited state
C
Hybridized state
2s
sp2
hybridization
+
sp2 sp2 sp2
unhybridized
2p orbital
C2H4
sp hybridization ethyne, C2H2
1s
2s
6C - 1s2 2s22p4
Ground state
sp
hybridization
+
unhybridized
2p orbital
C
sp sp
unhybridized 2p orbital
overlap form π bond
unhybridized 2p orbital
overlap form π bond
π bond
Video on hybridization
Click here to view hybridization Click here hybridization theory
22. sp2 hybridization methanal, H2CO
1s
1s
2s
2p
6C - 1s2 2s22p4
1s
2p
excited
Ground state Excited state
Hybridized state
2s
sp2
hybridization
+
sp2 sp2 sp2
unhybridized
2p orbital
C
unhybridized 2p orbital
overlap form π bond
C
Oxygen
sp2 hybridization
23. sp2 hybridization methanal, H2CO
2p
excited
2s
1s
2p
1s
1s
2s
2p
6C - 1s2 2s22p4
1s
2p
Ground state Excited state
Hybridized state
2s
sp2
hybridization
+
sp2 sp2 sp2
unhybridized
2p orbital
1s
2s
6C - 1s2 2s22p4
Ground state
sp
hybridization
+
unhybridized
2p orbital
sp sp
C
unhybridized 2p orbital
overlap form π bond
unhybridized 2p orbital carbon
overlap form π bond
sp hybridization carbon dioxide, CO2
C
sp hybridization C
sp2 hybridization O
C
Oxygen
sp2 hybridization
24. sp3 hybridization water H2O
1s
1s
2s
2p
8O - 1s2 2s22p4
1s
2p
excited
2s
sp3
hybridization
+
sp3 sp3 sp3 sp3
O
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 2 bonding pair/ 2 lone pair
- sp3 orbital oxygen overlap
with s orbital hydrogen
H2O
:
:
O
H H
25. sp3 hybridization water H2O
sp3 sp3 sp3 sp3
1s
1s
2s
2p
8O - 1s2 2s22p4
1s
2p
excited
2s
sp3
hybridization
+
sp3 hybridization phosphorus trichloride PCI3
2s
Ground state
1s
2p
1s
2s
2p
1s
excited
+
sp3 sp3 sp3
Excited state Hybridized state
O
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 2 bonding pair/ 2 lone pair
- sp3 orbital oxygen overlap
with s orbital hydrogen
15P - 1s2 2s22p63s23p3
sp3
+
:
:
H H
PCI3
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 3 bonding pair/1 lone pair
- sp3 orbital phosphorus overlap
with p orbital chlorine
H2O
3s
3p
3s
3p
2s
2p
sp3
hybridization CI 3p
O
P
P
:
P
CI
CI CI
26. hybridization sp3
2p
excited
2s
sp3
sp3 sp3 sp3
1s CI
1s 1s
PCI3
P
CI
CI
2s
2p
3s
3p
3s
3p
2s
2p
CI 3p
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 3 bonding pair/1 lone pair
- sp3 orbital phosphorus overlap
with p orbital chlorine
P
Phosphorus exist as PCI3 or PCI5
sp3 hybridization phosphorus trichloride PCI3
:
27. hybridization
2p
excited
2s
sp3
sp3 sp3 sp3
1s CI
1s 1s
sp3
dsp3 hybridization phosphorus pentachloride PCI5
2s
Ground state
1s
2p
1s
2s
2p
1s
excited
Excited state Hybridized state
15P - 1s2 2s22p63s23p3
PCI3
- Five dsp3 hybrid orbitals
- Trigonal bipyrimidal electron distribution
- 5 Bonding pair
- dsp3 orbital phosphorus overlap with p orbital chlorine
3s
3p
3s
3p
2s
2p
dsp3
hybridization
CI 3p
P
P
CI
CI
2s
2p
3s
3p
3s
3p
2s
2p
CI 3p
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 3 bonding pair/1 lone pair
- sp3 orbital phosphorus overlap
with p orbital chlorine
P
3d 3d
5 dsp3
+
Phosphorus exist as PCI3 or PCI5
sp3 hybridization phosphorus trichloride PCI3
✓ Expanded Octet
P
Click here to view
:
28. 2p
excited
2s
sp3
hybridization
1s 1s
sp3
SF2
S
F
F
1s
2s
2p
3s
3p
3s
3p
2s
sp3 sp3 sp3
2p
F 3p
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 2 bonding pair/2 lone pair
- sp3 orbital sulfur overlap
with p orbital fluorine
S
Sulfur exist as SF2, SF4 or SF6
sp3 hybridization SF2
::
29. 2p
excited
2s
sp3
hybridization
1s 1s
sp3
dsp3 hybridization SF4
2s
Ground state
1s
2p
1s
2s
2p
1s
excited
sp3 sp3 sp3
Excited state Hybridized state
15S - 1s2 2s22p63s23p6
SF2
S
::
- Five dsp3 hybrid orbitals
- Trigonal bipyrimidal electron distribution
- 4 bonding pair/1 lone pair
- dsp3 orbital sulfur overlap with p orbital fluorine
3s
3p
3s
3p
2s
2p
dsp3
hybridization
F 3p
S
S
F
F
1s
2s
2p
3s
3p
3s
3p
2s
2p
F 3p
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 2 bonding pair/2 lone pair
- sp3 orbital sulfur overlap
with p orbital fluorine
S
3d 3d
5 dsp3
+
Sulfur exist as SF2, SF4 or SF6
sp3 hybridization SF2
Expanded Octet
F
F
F
F
SF4
S
✓
30. 2p
excited
2s
sp3
hybridization
1s 1s
sp3
SF2
1s
2s
2p
3s
3p
3s
3p
2s
sp3 sp3 sp3
2p
F 3p
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 2 Bonding pair/2 lone pair
- sp3 orbital sulfur overlap
with p orbital fluorine
S
Sulfur exist as SF2, SF4 or SF6
sp3 hybridization SF2
F
F
:S:
31. 2p
excited
2s
sp3
hybridization
1s 1s
sp3
sp3 sp3 sp3
d2sp3 hybridization SF6
2s
Ground state
1s
2p
1s
2s
2p
1s
excited
Excited state Hybridized state
15S - 1s2 2s22p63s23p6
SF2
- Six d2sp3 hybrid orbitals
- Octahedral electron distribution
- 6 Bonding pair
- d2sp3 orbital sulfur overlap with p orbital fluorine
3s
3p
3s
3p
2s
2p
d2sp3
hybridization
F 3p
S
1s
2s
2p
3s
3p
3s
3p
2s
2p
F 3p
+
- Four sp3 hybrid orbitals
- Tetrahedral electron distribution
- 2 Bonding pair/2 lone pair
- sp3 orbital sulfur overlap
with p orbital fluorine
S
3d 3d
6 d2sp3
+
Sulfur exist as SF2, SF4 or SF6
sp3 hybridization SF2
Expanded Octet
SF6
3d
F
F
:S:
S
✓
32. IB Question
State the type of hybridization shaded in red
CO2 SO3 SO2
NH3 CH H2O H2CO 3COOH
CH4
CO2- 3
NO2
XeF2 CIF3 - BrF5 XeF4
:
State the hybridization shaded in red and number of sigma and pi bonds
sigma bonds pi bond
:
:
C :
:
:
C
:
33. IB Question
State the type of hybridization shaded in red
CO2 SO3 SO2
NH3 CH H2O H2CO 3COOH
sp2 sp2 sp3 sp2 sp3 sp2
CH4
CO2- 3
NO2
XeF2 CIF3 - BrF5 XeF4
sp
:
sp2 sp2 d2sp3 dsp3 dsp3 d2sp3 sp3
State the hybridization shaded in red and number of sigma and pi bonds
sigma bonds pi bond
:
C- sp2 N- sp3
C- sp2 C- sp2
:
C :
:
:
C
:
N- sp3 N- sp3
C - sp3
19 sigma bonds
2 pi bonds
12 sigma bonds
2 pi bonds
5 sigma bonds
1 pi bond
C- sp3
C- sp2
34. ECC Bonding
Pair
Lone
Pair
Electron Distribution
Electron geometry domain
Hybridization
s, p
VSEPR
Atomic
orbitals
Type of
Hybridization
sp
Number of
Hybrid orbitals
s, p, p
s, p, p, p
s, p, p, p, d
s, p, p, p, d, d
sp2
sp3
dsp3
d2sp3
linear
Trigonal
planar
Tetrahedral
Trigonal
Bipyrimidal
Octahedral
Shape/Geometry
linear
s, p, p sp2 Trigonal
planar
Tetrahedral
Tetrahedral
s, p, p, p
s, p, p, p
sp3
sp3
:
..
Trigonal
Bipyrimidal s, p, p, p, d dsp3
Trigonal
Bipyrimidal s, p, p, p, d dsp3
Trigonal
Bipyrimidal s, p, p, p, d dsp3
....
Octahedral
Octahedral
s, p, p, p, d, d
s, p, p, p, d, d
d2sp3
d2sp3
..
....
......
....
..
Trigonal
planar
Bend
V shape
Tetrahedral
Trigonal
pyrimidal
Bend
V shape
Trigonal
Bipyrimidal
Seesaw
T shape
Linear
Octahedral
Square
pyrimidal
Square
planar
35. Acknowledgements
Thanks to source of pictures and video used in this presentation
Thanks to Creative Commons for excellent contribution on licenses
http://creativecommons.org/licenses/
Prepared by Lawrence Kok
Check out more video tutorials from my site and hope you enjoy this tutorial
http://lawrencekok.blogspot.com