IB Chemistry on Lewis structure, ionic and covalent bonding

1. brown liquid
violet solid
Ionic Bonding Group 1 and 17
Gp 1 Metal2.1
2.8.1
2.8.8.1
2.8.8.18.1
Na
Li
K
Rb
Click here video on NaCI
yellow gas
greenish gas
Ionic bonding between metal and non metal
Metal
• Low EN value
• Lose electron (cation)
• Electropositive ions
Non metal
• High EN value
• Gain electron (anion)
• Electronegative ions
2.8.1 2.8.7
Gp 17 Non metal
transfer electron
2.8 2.8.8
achieve stable octet structure
+ -
Na+ CI-
Electrostatic force attraction
bet opposite charge ions
Crystal lattice structure
• +/- ion attract/ arranged in orderly manner
• arrangement in 3D shape
• strong electrostatic forces attraction
bet opposite charged ions
Reaction bet sodium with chlorine
Crystal lattice structure

2. violet solid
brown liquid
Gp 2 Metal
2.2
2.8.2
2.8.8.2
2.8.8.18.2
Mg
Be
Ca
Sr
Click here simulation ionic bonding
yellow gas
greenish gas
Ionic bonding between metal and non metal
Metal
• Low EN value
• Lose electron (cation)
• Electropositive ions
Non metal
• High EN value
• Gain electron (anion)
• Electronegative ions
2.8.2 2.7
Gp 17 Non metal
transfer electron
2.8
achieve stable octet structure
Mg2+ F-
Electrostatic force attraction
bet opposite charge ions
Crystal lattice structure
Crystal lattice structure
• +/- ion attract/arrange orderly manner
• arrangement in 3D shape
• strong electrostatic forces attraction
bet opposite charged ions
2.8. 82.8
F-

3. Cations/Metals/+ve ions
Gp1 Gp 2 Gp3 Transition metals ions
( variable oxidation states)
Oxidation
state
+1
Oxidation
state
+2
Oxidation
state
+3
Sc
+3
Ti
+2
+3
V
+2
+3
Cr
+2
+3
+6
Mn
+2
+3
+6
+7
Fe
+2
+3
Co
+2
+3
Ni
+2
Cu
+1
+2
Zn
+2
Li 1+ Be2+ Sc 3+ Ti 2+
Ti3+
V 2+
V 3+
Cr 2+
C r3+
Cr6+
Mn 2+
Mn 3+
Mn 6+
Mn 7+
Fe 2+
Fe 3+
Co2+ Ni2+ Cu1+
Cu2+
Zn2+
Na 1+ Mg2+ Al 3+
K 1+ Ca2+
Anion/Non metal
Gp 5 Gp 6 Gp 7
Oxidation
state
Oxidation
state
Oxidation
state
-3 -2 -1
N3- O2- F-1
P3- S2- CI-1
Br-1
I-1
Metal/Cations/+ve ion
Non Metal/
Anions/
-ve ion
Ionic Compound
Li2O MgCI2 Al2O3 FeO NiO CuO
Li3N Mg3N2 AlN Fe3N2 Ni3N2 Cu3N2
Oxidation state/Charge ion → Li1+
O2-
Formula compound Li2
O1
Video on polyatomic ions
Writing Chemical Formula Ionic Compounds
Step 1 : Write Oxidation state/charge
Step 2 : Balance it, (electrically neutral)
by cross multiply – as subscript

4. Polyatomic ions
Group of non-metals bonded together
Oxidation
state
Oxidation
state
Oxidation
state
-1/+1 -2 -3
(OH)-1
Hydroxide
(SO4)2-
Sulphate
(PO4)3-
Phosphate
(CN)-1
Cyanide
(SO3)2-
Sulphite
(SCN)-1
Thiocyanate
(CO3)2-
Carbonate
(NO3)-1
Nitrate
(S2O3)2-
Thiosulphate
(NO2)-1
Nitrite
(Cr2O7)2-
Dichromate
(NH4)+1
Ammonium
Polyatomic ions
Li2(CO3) Mg(CO3) Al2(CO3)3 Fe(CO3) Ni(CO3) Cu(CO3)
Li(OH) Mg(OH)2 Al(OH)3 Fe(OH)2 Ni(OH)2 Cu(OH)2
Li2(SO4) Mg(SO4) Al2(SO4)3 FeSO4 Ni(SO4) Cu(SO4) Video on polyatomic ions
Ionic Compound
Metal/Cations/+ve ions
Cations/Metals/+ve ions
Gp1 Gp 2 Gp3 Transition metals ions
( variable oxidation states)
Oxidation
state
+1
Oxidation
state
+2
Oxidation
state
+3
Sc
+3
Ti
+2
+3
V
+2
+3
Cr
+2
+3
+6
Mn
+2
+3
+6
+7
Fe
+2
+3
Co
+2
+3
Ni
+2
Cu
+1
+2
Li 1+ Be2+ Sc 3+ Ti 2+
Ti3+
V 2+
V 3+
Cr 2+
C r3+
Cr6+
Mn 2+
Mn 3+
Mn 6+
Mn 7+
Fe 2+
Fe 3+
Co2+ Ni2+ Cu1+
Cu2+
Na 1+ Mg2+ Al 3+
K 1+ Ca2+
Oxidation state/Charge ion → Li1+
(CO3)2-
Formula compound Li2
(CO3
)1
Step 1 : Write Oxidation state/charge ion
Step 2 : Balance it, (electrically neutral)
by cross multiply – as subscript
Writing Chemical Formula Ionic Compounds

5. Acids Alkali
Metal Hydroxide
Metal oxides Salts Gas
HCI
Hydrochloric acid
KOH
Potassium hydroxide
CuO
Copper(II) oxide
CaCO3
Calcium carbonate
CO
Carbon monoxide
HNO3
Nitric acid
NaOH
Sodium hydroxide
MgO
Magnesium oxide
Na2CO3
Sodium carbonate
CO2
Carbon dioxide
H2SO3
Sulphurous acid
Ca(OH)2
Calcium Hydroxide
ZnO
Zinc oxide
NaHCO3
Sodium bicarbonate
SO2
Sulphur dioxide
HCOOH
Methanoic acid
NH3
Ammonia
Na2O
Sodium oxide
KNO3
Potassium nitrate
SO3
Sulphur trioxide
CH3COOH
Ethanoic acid
Mg(OH)2
Magnesium hydroxide
Al2O3
Aluminium oxide
Pb(NO3)2
Lead (II) Nitrate
NO2
Nitrogen dioxide
H3PO4
Phosphoric acid
Cu(OH)2
Copper (II) hydroxide
Fe2O3
Iron(III) oxide
NaNO3
Sodium nitrate
CH4
Methane
H2CO3
Carbonic acid
Al(OH)3
Aluminium hydroxide
K2S
Potassium sulphide
PbI2
Lead (II) nitrate
H2S
Hydrogen sulphide
HNO2
Nitrous acid
Fe(OH)2
Iron (II) hydroxide
PbS
Lead(II) sulphide
AgCI
Silver chloride
O2
Oxygen
HF
Hydrofluoric acid
Fe(OH)3
Iron (III) hydroxide
ZnS
Zinc sulphide
MgSO4
Magnesium sulphate
N2
Nitrogen
HCIO
Hypochlorous acid
Zn(OH)2
Zinc hydroxide
AI2S3
Aluminium sulphide
Na2S2O3
Sodium thiosulphate
CI2
Chlorine
Chemical Formula for common chemicals
Naming chemical compoundWriting chemical formulaWriting chemical formula
VIDEO TUTORIALS

6. violet solid
brown liquid
Click here simulation on covalent bond
yellow gas
greenish gas
Covalent bonding between non metals
2.8.7
Gp 17 Non metal
achieve stable octet structure
CI shared pair electron
Covalent Bonding
Electrostatic forces attraction between
nucleus with 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
Covalent Bond Group 17
CICI
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
CI CI: x
x
::
:.
x
x
X
x
x
x
x CI CI
::
x
x
x
x
CI CI
Non metal
• High EN value
• Gain electron (anion)
• Electronegative ions
Single covalent bond – shared pair electron

7. Covalent bonding between non metals
Covalent Bonding
Single covalent bond
ONE pair shared e
2.8.8 2.8.8
Covalent Bond
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
CI CI:
x
x
::
:
:
.
x
x
X
X
x
x
x
x
x
x
O
CI CI::
x
x
x
x
x
x
CI CI
Sharing
electron
Bond Strength
2.8 2.8
Sharing
electron
O O: x
x O
N
O O
N:
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
C
: :. N N: N N
:
Covalent Bonding
Double covalent bond
TWO pair shared e
Covalent Bonding
Triple covalent bond
THREE pair shared e
O
x
x: CO CO O O O
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
Covalent Bonding
Double covalent bond
TWO pair shared e

8. :
CI
..
x
Bond Bond
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
CI CI:
x
x
::
:
:
.
x
x
X
X
x
x
x
x
O
CI CI::
x
x
x
x
x
x
CI CI
O O: x
x O
N
O O
N:
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
Lewis structure/diagram
. Electron cross dot
. Valence/bonding pair electron
O
: :
.
N N: N N
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
C O: :
Bonding pair electron
Dative bond
(electron pair of oxygen)
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
Expanded octet
More than 8 valence e
All period 3 element
- observe octet rule
except P and S
: BeCI CIx
. :
::
::
.
X
x.
Be - 4 valence e
BCI CI
:
::
:
:: x
::B - 6 valence e
P S
CI
CI
CI
CI
CI
CI
CICI
CICI
CI
P - 10 valence e
S – 12 valence e

9. O
ONO C
N
C BeH N
B
 X
 x
C SSO
Linear
O C H H NO N O
Trigonal
planar
C OO CH N HH Be C N N O O:x
x 
X
x
X
x
 X
X 
X 
X 
X
X
 X
 x
X
x
+
+
: :
.
F
F
F
Electron deficient Be
Dative bond from N
NCx
x :
Electron deficient N
(7 valence electron)
H
H O O
O O
O O
C
O O
O
O N
O
O
B XF
F
F
C
H
H
x
x
O S
O O
S
O O:::
:
:
O
C
O
x
x
O N
2- -
2-
O
:
: :
x
x
O
:
: :
O
-
Electron deficient B
O
S
O
:
:
O:
:
::
Dative bond from S
:
ON
O
O
:
:
-
O
X
X
|| ||
Sulphur
expanded octet
(12 valence electron) ✓
BF3 CH2 O SO3 CO3
2- NO3
-
CO2 HCN BeH2 CN - NO2
+ NO
::
X
X
X
X
Dative bond from N

10. O
O
O
O
O O
:
:

N
:
:
O O
O
N
O

S
O O
OO
S
:
S
O O
OO
S
:
:
N
O O
N
OO
-
-
O O
N

O
O
N
:
-
Dative bond from N
electron deficient N
(7 valence electron)
S
O O
:
:
Sulphur
expanded octet
(10 valence electron)
or
or
Dative bond from S
NO2
-NO2 SO2O3
O
HH
H2O
H H
O
O
F2O
F F
F F
O
S
CICI
SCI2 SH2
S
H H
S
CI CI
S
H
NH2
-
N
HH
HH
N
-
-
H: : : : :
:
:
:
:
: :
All molecule – octet rule
Bend
Bend
O
O
:
O
Dative bond from O

11. ||
:
S
CI
Sulphur
expanded octet
(12 valence electron)
C
H
H
CH4 NH4
+
N
BH4
- PCI4
+ POCI3
P
CI
-+
Tetrahedral
H
H
H
H
H
H
B
H
H
HH CI
CICI
+
P
O
CI
CICI
C
H

H
H
H
H
N

H
H
H
+

H
B
H
H
H
-
CI

P
CI
CI
CI
+
:
:
:
:
:
::
:
: :
:
:
O
::
P
CI
CI
::
:
:
:
:
: :
O
SO4
2-
O
O
O
O
S
O
::
O
||
O
H2SO4 H3PO4 CIO4
-
||
O
S
O
S
O
O
::
O
||
P
OH
O
::
P
||
O
CI
O
O
O
O
CI
::
OO
O
-
-
Phosphorus
expanded octet
(10 valence electron)
Chlorine
expanded octet
(14 valence electron)
Tetrahedral
2-
2-

12. N
H
N
:
:
O
SO3
2-PH3NH3
O
HH
H2O
H H
O
O
F2O
F F
F F
O
S
CICI
SCI2 SH2
S
H H
S
CI CI
S
H
NH2
-
N
HH
HH
N
-
-
H: : : : :
:
:
:
:
: :
Two lone pair
central atom
Bend
CIO3
-
H
H
P
H
H
H
H
H
H
P
H
H
H
:
O
O
S
O
S
O
:
O
2-
2-
CI
O
O
O
CI
:
O
O
O
-
:
-
SOCI2
S
CI
CI
O
S
:
O
CI
CI
:
: :
::
:
One lone pair
central atom
One lone pair
Pyrimidal
Two lone pair
CH4
C
H
NH4
+ BH4
- PCI4
+ POCI3
H
H
H
H
C
H
H
H

N
H
H H
H
H
N
H
H
H

H
B
HH H
H
B
H

H
H
CI
CI CI CI
P
CI
CI
CI
P

CI
O-
-
+
+
+
+
P
CI CICI
||
CI CI
CI
O
P
::
Tetrahedral
NO lone pair
:
:
:
:
::
::
:
::
:
::
::
: :
::
:
NO lone pair
central atom

13. P CI
CI
CI
CI
CI
:
P

CI
 CI
CI
CI

Seesaw
structure
T
structure

S
F
F
F
F
S
F


F
F
F
Te
CI
CI
CI
CI
Te
CI
CI
CI
CI
:
CI
F
F
F
CI
F

F
F

I
CI
CI
CI
CI
I


CI

CI
I
F
F
F
F
F
I

F
F

F
Xe
F
F
O
O
Xe

F

F
O
O
:
+
+
:
CI
Linear
structure


I
I
I


Xe
CI
CI
I

F
F

:::::::
:
:
::
::
::
:
:
:
:
:
::
:
:
::
:
:
:
:
:
:
:
::
:
::::
:
:
::
:
::
:
::
::
:
::
:
::
:
::
::
::
::
::
::
::
::
::
:
: : :
NO lone pair
NO lone pair
central atom
ONE lone pair
:
ONE lone pair
central atom
TWO lone pair
TWO lone pair
central atom
THREE lone pair
THREE lone pair
central atom
:
BrF
F
F
Br
F



F
F
: :
:
: :
:
::
:
-
PCI5
SF4
TeCI4 (IF4)+ XeO2F2
CIF3 ICI3 BrF3
(I3)- (ICI2)- XeF2
Trigonal
bipyrimidal
Central atom S, Te, I, Xe
- expanded octet
- 10 valence electron
Central atom P
- expanded octet
- 10 valence electron
Central atom CI, I, Br
- expanded octet
- 10 valence electron
Central atom I and Xe
- expanded octet
- 10 valence electron
-

14. Octahedral
F
S
SF6
F
F
F
F
F
PCI6
-
P
CI
CI
CI
CI
CI
CI
IF5O
I
O
||
F
F
F
F
F
F

S
F

F
F
F
F
CI
P
CI


CI
CI
CI
CI
I
F
F
F

F
F
::
O
NO lone pair
Square
pyrimidal

CI
Sb
Sb
CI
CI
CICI
CI
CI
CICI
CI
(SbCI5)2- BrF5
Xe
F
FF
F
Xe
F
XeF4
F
F
F
F
Br
F
FF
F
F
Br
 F
F
O
F
F
Xe
||
F
FF
F
O
::
Xe
F
F
F
F
F
Te
F
FF
F
F

Te
F
F
F
F
XeOF4 (TeF5)-
-
-
CICI
I
CICI
(ICI4)-
-
I
CI
CI
CI
CI
-Square
planar
:
:
:
:
:::
ONE lone pair
TWO lone pair
:
:
::
:
:
:
::
:::
:
::
:
::::
::
:
:
:
:
:
:
:
::
:
:
:
:
::
: :::
:
:
:
:
::
:
::
:
::::
:
::::
::::
:
:
:
::
::
:
::
:
:
::::
::::
:
:
:::
::::
:
::
:
:
:
:
:
:
::
:::
::::
:
2-
2-
::::
::::
:
:
:
:
::
::
::::
::::
::
::
NO lone pair
central atom
Central atom S, P , I
- expanded octet
- 12 valence electron
ONE lone pair
central atom
Central atom Sb, Br, Xe, Te
- expanded octet
- 12 valence electron
TWO lone pair
central atom
Central atom Xe, I
- expanded octet
- 12 valence electron
-
-

15. Chemical Bonds
Achieve stable electron arrangement of noble gases
Ionic Bonds
Transfer of electron from
metal to non metal
Metal donate e Non Metal accept e
Positive ion
(cation)
Negative ion
(anion)
Ionic compound
Solubility
Covalent Bonds
Sharing of electron
bet non metal atoms
Covalent compound/molecules
Non Metal share electrons
Difference in physical property
m/p + b/pconductivityVolatility
+ -electrostatic forces
attraction
Concept Map
Volatility Solubility Conductivity M/p
B/p
Ionic
compound
Low  Soluble in aqueous
solvent
High 
(In aqueous)
High 
Covalent
compound
High  Soluble in organic
solvent
Low  Low 
0 0.4 4
Difference in electronegativity
difference < 0.4
covalent compound
difference > 2
ionic compound
2
CI-Na+
EN - 0.9 EN - 3.0
Diff = 3 – 0.9
= 2.1
C
2.5
H
2.1
EN – 2.5 EN – 2.1
Diff = 2.5 – 2.1
= 0.4