4.11.24 Mass Incarceration and the New Jim Crow.pptx
IB Chemistry on Periodic Trends, Effective Nuclear Charge and Physical properties.
1. Tutorial on Periodic Trend, Effective Nuclear
Charge and Physical Properties for Period 2
and 3.
Prepared by
Lawrence Kok
http://lawrencekok.blogspot.com
2. Periodic Table of elements – divided to Groups, Periods and Blocks
Period- Horizontal row
• 7 periods/row
• Same number of shell
Group 1
Periods
1
7
Groups – Vertical column
• Same number of valence electron
• Same number outmost electrons
Block – different region in periodic table
• s, p, d, f blocks
• s block- elements with valence e in s sublevel
• p block – elements with valence e in p sublevel
18
3. Periodic Table of elements – divided to Groups, Periods and Blocks
Period- Horizontal row
• 7 periods/row
• Same number of shell
Groups – Vertical column
• Same number of valence electron
• Same number outmost electrons
Block – different region in periodic table
• s, p, d, f blocks
• s block- elements with valence e in s sublevel
• p block – elements with valence e in p sublevel
Group 1
18
Periods
1
7
Excellent site from periodic videos
Click here to view
s block
- s orbitals partially fill
d block
• d orbitals partially fill
p block
• p orbital partially fill
f block
• f orbital partially fill
4. s block elements
• s orbitals partially fill
1
H
He
p block elements
• p orbital partially fill
5
1s2
n = 2 period 2
B
[He] 2s2 2p1
6
1s1
2
Periodic Table – s, p d, f blocks elements
C
[He] 2s2 2p2
7
N
[He] 2s2 2p3
3
Li
[He] 2s1
8
O
[He] 2s2 2p4
4
Be
[He] 2s2
9
F
[He] 2s2 2p5
10
Ne
[He] 2s2 2p6
13
Al
[Ne] 3s2 3p1
3s1
11
Na
[Ne]
12
Mg
[Ne] 3s2
14
20
K
Ca
[Ne] 3s2 3p2
[Ar]
15
P
[Ne] 3s2 3p3
[Ar]
4s2
16
S
[Ne] 3s2 3p4
17
19
Si
4s1
CI
[Ne] 3s2 3p5
18
Ar
[Ne] 3s2 3p6
d block elements
• d orbitals partially fill
• transition elements
21
Sc
[Ar] 4s2 3d1
22
Ti
[Ar] 4s2 3d2
23
V
[Ar] 4s2 3d13
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
f block elements
• f orbitals partially fill
5. s block elements
• s orbitals partially fill
1
H
He
p block elements
• p orbital partially fill
5
1s2
n = 2 period 2
B
[He] 2s2 2p1
6
1s1
2
Periodic Table – s, p d, f blocks elements
C
[He] 2s2 2p2
7
N
[He] 2s2 2p3
3
Li
[He] 2s1
8
O
[He] 2s2 2p4
4
Be
[He] 2s2
9
F
[He] 2s2 2p5
10
Ne
[He] 2s2 2p6
13
Al
[Ne] 3s2 3p1
3s1
11
Na
[Ne]
12
Mg
[Ne] 3s2
14
20
K
Ca
[Ne] 3s2 3p2
[Ar]
15
P
[Ne] 3s2 3p3
[Ar]
4s2
16
S
[Ne] 3s2 3p4
17
19
Si
4s1
CI
[Ne] 3s2 3p5
18
Ar
[Ne] 3s2 3p6
d block elements
• d orbitals partially fill
• transition elements
21
Sc
[Ar] 4s2 3d1
22
Ti
[Ar] 4s2 3d2
23
V
[Ar] 4s2 3d13
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
f block elements
• f orbitals partially fill
Video on electron configuration
Click here electron structure
Click here video on s,p,d,f notation
Click here video s,p,d,f blocks,
6. Periodicity
Predicted pattern/trends in physical/chemical properties across period.
Physical properties
Physical change - without change in molecular composition.
– appearance change
- composition remain unchanged.
Element properties
•
•
•
•
•
Color, texture, odor
Density, hardness, ductility
Brittleness, Malleability
Melting /boiling point
Solubility, polarity
Atomic properties
•
•
•
•
Ionization energy
Atomic radii
Ionic radii
Electronegativity
Chemical properties
Chemical change – diff composition from original substances
- chemical bonds broken/ formed
- new products formed
7. Periodicity
Predicted pattern/trends in physical/chemical properties across period.
Physical properties
Chemical properties
Physical change - without change in molecular composition.
– appearance change
- composition remain unchanged.
Element properties
•
•
•
•
•
Atomic properties
•
•
•
•
Color, texture, odor
Density, hardness, ductility
Brittleness, Malleability
Melting /boiling point
Solubility, polarity
•
•
Ionization
energy
Periodic Trends
Across period 2/3
Down group 1/17
Atomic/ionic
radii
Gp 1
Ionization energy
Atomic radii
Ionic radii
Electronegativity
Melting
point
Electronegativity
Gp 17
period 2
period 3
Chemical change – diff composition from original substances
- chemical bonds broken/ formed
- new products formed
8. Ionization energy (IE)
1st Ionization energy
Min energy to remove 1 mole e from
1 mole of element in gaseous state
M(g) M+ (g) + e
2nd Ionization energy
Min energy to remove 1 mole e from
1 mole of +1 ion to form +2 ion
M+(g) M2+ (g) + e
Ionization energy
Why IE increases across the period?
Why IE decreases down a group ?
9. Ionization energy (IE)
1st Ionization energy
Min energy to remove 1 mole e from
1 mole of element in gaseous state
M(g) M+ (g) + e
2nd Ionization energy
Min energy to remove 1 mole e from
1 mole of +1 ion to form +2 ion
M+(g) M2+ (g) + e
Ionization energy
Factors affecting ionization energy
1
Distance from nucleus
electron
Distance near to nucleus – IE High
Distance far away nucleus – IE Low
Distance near
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Why IE increases across the period?
Why IE decreases down a group ?
10. Why IE increases across the period?
Why IE decreases down a group ?
Ionization energy (IE)
1st Ionization energy
Min energy to remove 1 mole e from
1 mole of element in gaseous state
M(g) M+ (g) + e
2nd Ionization energy
Min energy to remove 1 mole e from
1 mole of +1 ion to form +2 ion
M+(g) M2+ (g) + e
Ionization energy
Factors affecting ionization energy
1
2
Distance from nucleus
Nuclear charge
electron
+3
+4
+5
+6
Nuclear charge increase
Distance near to nucleus – IE High
Distance far away nucleus – IE Low
Nuclear charge high (more proton) – IE High
Nuclear charge low (less proton) – IE Low
+6
Distance near
Nuclear charge
Strong electrostatic forces
attraction bet nucleus and e
Strong electrostatic forces
attraction bet nucleus and e
IE – High
IE – High
11. Why IE increases across the period?
Why IE decreases down a group ?
Ionization energy (IE)
1st Ionization energy
Min energy to remove 1 mole e from
1 mole of element in gaseous state
M(g) M+ (g) + e
2nd Ionization energy
Min energy to remove 1 mole e from
1 mole of +1 ion to form +2 ion
M+(g) M2+ (g) + e
Ionization energy
Factors affecting ionization energy
1
2
Distance from nucleus
3
Nuclear charge
electron
+3
+4
+5
+6
Effective Nuclear Charge (ENC)/(Zeff)
• Screening effect/shielding
• Effective nuclear charge (ENC)/(Zeff)
(Zeff) = Nuclear charge (Z) – shielding effect
• Net positive charge felt by valence electrons.
Nuclear charge increase
Distance near to nucleus – IE High
Distance far away nucleus – IE Low
Nuclear charge high (more proton) – IE High
Nuclear charge low (less proton) – IE Low
+6
Inner electron – shield valence e from positive nuclear charge
Distance near
Nuclear charge
Higher electron/electron repulsion
Strong electrostatic forces
attraction bet nucleus and e
Strong electrostatic forces
attraction bet nucleus and e
Easier valence e to leave
IE – High
IE – High
IE – Low
12. IE drop from Be to B and N to O
Ionization Energy- Period 2
Why IE increases across the period 2?
IE increases across period 2
Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
1s2 2s2 2p2
1s2 2s2 2p3
1s2 2s2 2p4
1s2 2s2 2p5
1s2 2s2 2p6
13. IE drop from Be to B and N to O
Ionization Energy- Period 2
Why IE increases across the period 2?
IE increases across period 2
Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
IE drop from Be to B
Electron in p sublevel of B
– further away from nucleus
Weak electrostatic force attraction
between nucleus and electron
IE - Low
1s2 2s2 2p2
1s2 2s2 2p3
1s2 2s2 2p4
1s2 2s2 2p5
1s2 2s2 2p6
14. IE drop from Be to B and N to O
Ionization Energy- Period 2
Why IE increases across the period 2?
IE increases across period 2
Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
1s2 2s2 2p2
IE drop from Be to B
1s2 2s2 2p3
1s2 2s2 2p4
IE drop from N to O
Electron in p sublevel of B
– further away from nucleus
2 electrons in same p orbital
- Greater e/e repulsion
Weak electrostatic force attraction
between nucleus and electron
Easier to remove e
IE - Low
IE - Low
period 2
1s2 2s2 2p5
1s2 2s2 2p6
15. IE drop from Mg to AI and P to S
Ionization Energy- Period 3
Why IE increases across the period 3?
IE increases across period 3
Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Na
Mg
AI
Si
P
S
CI
Ar
3p
3s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p1
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
[Ne] 3s2 3p5
[Ne] 3s2 3p6
16. IE drop from Mg to AI and P to S
Ionization Energy- Period 3
Why IE increases across the period 3?
IE increases across period 3
Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Na
Mg
AI
Si
P
S
CI
Ar
3p
3s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p1
IE drop from Mg to AI
Electron in p sublevel of AI
– further away from nucleus
Weak electrostatic force attraction
between nucleus and electron
IE - Low
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
[Ne] 3s2 3p5
[Ne] 3s2 3p6
17. IE drop from Mg to AI and P to S
Ionization Energy- Period 3
Why IE increases across the period 3?
IE increases across period 3
Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
IE – High
Na
Mg
AI
Si
P
S
CI
Ar
3p
3s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p1
[Ne] 3s2 3p2
IE drop from Mg to AI
[Ne] 3s2 3p3
[Ne] 3s2 3p4
IE drop from P to S
Electron in p sublevel of AI
– further away from nucleus
2 electrons in same p orbital
- Greater e/e repulsion
Weak electrostatic force attraction
between nucleus and electron
Easier to remove e
IE - Low
IE - Low
Period 3
[Ne] 3s2 3p5
[Ne] 3s2 3p6
18. IE for Period 2 and 3
Ionization Energy- Period 2 and 3
Why IE period 3 lower than 2?
Period 3 – 3 shells/energy level
period 2
Period 3
Valence e further from nucleus
High shielding effect – more inner e
Weaker electrostatic forces
attraction bet nucleus and e
IE – Lower
period 2
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
1s2 2s2 2p2
1s2 2s2 2p3
1s2 2s2 2p4
1s2 2s2 2p5
1s2 2s2 2p6
Period 3
Na
Mg
AI
Si
P
S
[Ne] 3s2 3p1
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
CI
Ar
3rd level
3p
3s
2p
2s
1s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p5
[Ne] 3s2 3p6
19. IE for Period 2 and 3
Ionization Energy- Period 2 and 3
Why IE period 3 lower than 2?
Period 3 – 3 shells/energy level
period 2
Period 3
Valence e further from nucleus
High shielding effect – more inner e
Weaker electrostatic forces
attraction bet nucleus and e
IE – Lower
period 2
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
1s2 2s2 2p2
1s2 2s2 2p3
1s2 2s2 2p4
1s2 2s2 2p5
1s2 2s2 2p6
Period 3
Na
Mg
AI
Si
P
S
[Ne] 3s2 3p1
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
CI
Ar
3rd level
3p
3s
2p
2s
1s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p5
[Ne] 3s2 3p6
20. IE for Ne and Ar
Ionization Energy- Period 2 and 3
Why Ne and Ar have HIGH IE ?
Full electron configuration, 2.8/2.8.8
neon
argon
Most energetically stable structure
Difficult to lose electron
IE – High
period 2
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
1s2 2s2 2p2
1s2 2s2 2p3
1s2 2s2 2p4
1s2 2s2 2p5
1s2 2s2 2p6
Period 3
Na
Mg
AI
Si
P
S
[Ne] 3s2 3p1
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
CI
Ar
3p
3s
2p
2s
1s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p5
[Ne] 3s2 3p6
21. IE for Ne and Ar
Ionization Energy- Period 2 and 3
Why Ne and Ar have HIGH IE ?
Full electron configuration, 2.8/2.8.8
neon
argon
Most energetically stable structure
Difficult to lose electron
IE – High
period 2
Li
Be
B
C
N
O
F
Ne
2p
2s
1s
1s2 2s1
1s2 2s2
1s2 2s2 2p1
1s2 2s2 2p2
1s2 2s2 2p3
1s2 2s2 2p4
1s2 2s2 2p5
1s2 2s2 2p6
Period 3
Na
Mg
AI
Si
P
S
[Ne] 3s2 3p1
[Ne] 3s2 3p2
[Ne] 3s2 3p3
[Ne] 3s2 3p4
CI
Ar
3p
3s
2p
2s
1s
[Ne] 3s1
[Ne] 3s2
[Ne] 3s2 3p5
[Ne] 3s2 3p6
22. Atomic Radius
Distance between nucleus and outmost electrons.
✔
Atom not like a ball – can’t measure its radius directly
Uncertain about position of electron – uncertain of atomic radius
Uncertain abt electrons position
How to measure atomic radius?
Half the distance bet nuclei of two closest identical atoms.
✗
Atomic radius
23. Atomic Radius
Distance between nucleus and outmost electrons.
✗
✔
Atomic radius
Atom not like a ball – can’t measure its radius directly
Uncertain about position of electron – uncertain of atomic radius
Uncertain abt electrons position
How to measure atomic radius?
Half the distance bet nuclei of two closest identical atoms.
Atomic Radius
Covalent Molecule
Noble gas
Monoatomic atoms
Depend on type of bonding – covalent or metallic
Metallic elements
Ionic compounds
½ bond length
½ bond length
½ bond length
Covalent Radius
Van Der Waals radius
½ bond length of 2 atom
½ bond length of nuclei atoms
not bonded together (noble gas)
Metallic radius
½ bond length bet nuclei of
neighbouring metal ions
Ionic radius
Measure indirectly using
internucleus distance
24. Atomic Radius
Distance between nucleus and outmost electrons.
Atomic radius
✗
✔
Atom not like a ball – can’t measure its radius directly
Uncertain about position of electron – uncertain of atomic radius
Uncertain abt electrons position
How to measure atomic radius?
Half the distance bet nuclei of two closest identical atoms.
Atomic Radius
Covalent Molecule
Noble gas
Monoatomic atoms
Depend on type of bonding – covalent or metallic
Metallic elements
Ionic compounds
½ bond length
½ bond length
½ bond length
Covalent Radius
Van Der Waals radius
½ bond length of 2 atom
½ bond length of nuclei atoms
not bonded together (noble gas)
Click here video on atomic radius
Metallic radius
½ bond length bet nuclei of
neighbouring metal ions
Click here video on atomic radius
Ionic radius
Measure indirectly using
internucleus distance
Click here video on atomic radius
25. Effective Nuclear Charge (ENC)/(Zeff)
• Screening effect/shielding
• Effective nuclear charge (ENC)/(Zeff)
(Zeff) = Nuclear charge (Z) – shielding effect
• Net positive charge felt by valence electrons.
Effective nuclear charge
Effective nuclear charge
magnesium (2.8.2)
net +2
10 inner electron shield 12+ protons
Valence electron feel a net (12-10 = +2)
Effective nuclear charge, (Zeff) = +2
26. Effective Nuclear Charge (ENC)/(Zeff)
• Screening effect/shielding
• Effective nuclear charge (ENC)/(Zeff)
(Zeff) = Nuclear charge (Z) – shielding effect
• Net positive charge felt by valence electrons.
Effective nuclear charge
Effective nuclear charge
magnesium (2.8.2)
net +2
10 inner electron shield 12+ protons
Valence electron feel a net (12-10 = +2)
Calculate Z(eff) and atomic radius for Li
Effective nuclear charge, (Zeff) = +2
1
Calculate Z(eff) for Li
Formula
ionization energy
2nd energy level
n=2
æ Z2 ö
IE =1312 ç 2 ÷
èn ø
æ Z2 ö
521 =1312 ç 2 ÷
è2 ø
Zeff = +1.26
1st IE Li = 521kJ/mol
2 inner electron shield 3+ protons
Valence electron felt a net (3-2) = +1
Z(eff) = +1.26 NOT +1
(calculation shown above)
Lithium (2.1)
27. Effective Nuclear Charge (ENC)/(Zeff)
• Screening effect/shielding
• Effective nuclear charge (ENC)/(Zeff)
(Zeff) = Nuclear charge (Z) – shielding effect
• Net positive charge felt by valence electrons.
Effective nuclear charge
Effective nuclear charge
magnesium (2.8.2)
net +2
10 inner electron shield 12+ protons
Valence electron feel a net (12-10 = +2)
Calculate Z(eff) and atomic radius for Li
Effective nuclear charge, (Zeff) = +2
1
2
Calculate Z(eff) for Li
Formula
ionization energy
2nd energy level
n=2
Lithium (2.1)
æ Z2 ö
IE =1312 ç 2 ÷
èn ø
æ Z2 ö
521 =1312 ç 2 ÷
è2 ø
Zeff = +1.26
1st IE Li = 521kJ/mol
2 inner electron shield 3+ protons
Valence electron felt a net (3-2) = +1
Z(eff) = +1.26 NOT +1
(calculation shown above)
R
Calculate atomic radius Li using Z(eff)
Fcentripetal = Fcoulomb
mv 2 kqZ
= 2
r
R
2
mh
kqZ
=
m 2p 2 R 2
R
h2
R=
mp 2 kqZ
R =168pm
h h
l= =
p mv
h
v=
ml
v=
h
2nd energy level
n=2
n=2
2 l = 2p R
l =pR
mp R
m = mass electron -9.1 x 10-31
h = plank constant – 6.626 x 10-34
k = coulomb constant – 9.0 x 109
q = charge electron – 1.6 x 10-19
Z = effective nuclear charge - +1.26
28. Effective Nuclear Charge (ENC)/(Zeff)
• Screening effect/shielding
• Effective nuclear charge (ENC)/(Zeff)
(Zeff) = Nuclear charge (Z) – shielding effect
• Net positive charge felt by valence electrons.
Effective nuclear charge
Effective nuclear charge
magnesium (2.8.2)
net +2
10 inner electron shield 12+ protons
Valence electron feel a net (12-10 = +2)
Calculate Z(eff) and atomic radius for Li
Effective nuclear charge, (Zeff) = +2
1
2
Calculate Z(eff) for Li
Formula
ionization energy
2nd energy level
n=2
Lithium (2.1)
æ Z2 ö
IE =1312 ç 2 ÷
èn ø
æ Z2 ö
521 =1312 ç 2 ÷
è2 ø
Zeff = +1.26
1st IE Li = 521kJ/mol
2 inner electron shield 3+ protons
R
Calculate atomic radius Li using Z(eff)
Fcentripetal = Fcoulomb
mv 2 kqZ
= 2
r
R
2
mh
kqZ
=
m 2p 2 R 2
R
h2
R=
mp 2 kqZ
R =168pm
h h
l= =
p mv
h
v=
ml
v=
h
2nd energy level
n=2
n=2
2 l = 2p R
l =pR
mp R
m = mass electron -9.1 x 10-31
h = plank constant – 6.626 x 10-34
k = coulomb constant – 9.0 x 109
q = charge electron – 1.6 x 10-19
Z = effective nuclear charge - +1.26
Valence electron felt a net (3-2) = +1
Z(eff) = +1.26 NOT +1
(calculation shown above)
Click here video ENC Li
Click here video calculating radius Li
29. Atomic Radius (Covalent radius)
Atomic Radius- Period 2/3
Why atomic radius decrease across period 2/3
Atomic radius decrease across period 2/3
Effective Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
Size decrease
30. Atomic Radius (Covalent radius)
Atomic Radius- Period 2/3
Why atomic radius decrease across period 2/3
Atomic radius decrease across period 2/3
Effective Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
Size decrease
Li
+3
Be
+4
C
+6
N
+7
O
+8
F
+9
Effective Nuclear charge increase
period 2
Na
+11
period 3
B
+5
Mg
+12
AI
+13
Si
+14
Effective Nuclear charge increase
P
+15
S
+16
CI
+17
31. Atomic Radius (Covalent radius)
Atomic Radius- Period 2/3
Why atomic radius decrease across period 2/3
Atomic radius decrease across period 2/3
Effective Nuclear charge increase
Strong electrostatic forces
attraction bet nucleus and e
Size decrease
Gp 17
Li
+3
Be
+4
C
+6
N
+7
F
+9
O
+8
Effective Nuclear charge increase
period 2
Na
+11
period 3
B
+5
Mg
+12
AI
+13
Si
+14
P
+15
S
+16
CI
+17
Effective Nuclear charge increase
Why atomic radius increase down Gp 17?
Screening/shielding effect increase
Inner shell electrons
electron electron repulsion increase
Number shell increase
Valence e further away from nucleus
Atomic radius High
32. Positive Ions (+)
Atomic and Ionic Radius- Period 2/3
Ionic radii Positive ion (+) smaller
Decrease in number of shells – loss of electron
Less electron electron repulsion
Size decrease
Comparison bet atomic/ionic radii
Ionic radii
Atomic radii
33. Positive Ions (+)
Atomic and Ionic Radius- Period 2/3
Ionic radii Positive ion (+) smaller
Negative Ions (-)
Ionic radii Negative ion (-) bigger
Decrease in number of shells – loss of electron
Increase in number of shells – gain of electron
Less electron electron repulsion
Increase electron electron repulsion
Size decrease
Size increase
Comparison bet atomic/ionic radii
Comparison bet atomic/ionic radii
Ionic radii
Ionic radii
Atomic radii
Atomic radii
34. Positive Ions (+)
Atomic and Ionic Radius- Period 2/3
Ionic radii Positive ion (+) smaller
Negative Ions (-)
Ionic radii Negative ion (-) bigger
Decrease in number of shells – loss of electron
Increase in number of shells – gain of electron
Less electron electron repulsion
Increase electron electron repulsion
Size decrease
Size increase
Comparison bet atomic/ionic radii
Comparison bet atomic/ionic radii
Ionic radii
Ionic radii
Atomic radii
Atomic radii
Na
2.8.1
Na+
2.8
Mg
2.8.2
Mg2+
2.8
AI
2.8.3
AI3+
2.8
Atomic radii
- 3 shells
Ionic radii
- 2 shells
S
CI
2.8.6
2.8.7
S2-
CI-
2.8.8
2.8.8
Atomic radii
- 3 shells
Ionic radii
- 2 shells
35. Electronegativity
•
•
Electronegativity (EN)
Tendency of atom to attract/pull shared/bonding electron to itself
EN value higher – pull/attract electron higher (EN value from 0.7 – 4)
Shared electron cloud closer to O
•
•
EN lowest
EN highest
Electronegativity
EN increase up a Group
EN increase across a Period
36. Electronegativity
Electronegativity (EN)
Tendency of atom to attract/pull shared/bonding electron to itself
EN value higher – pull/attract electron higher (EN value from 0.7 – 4)
•
•
Shared electron cloud closer to O
•
•
EN highest
EN lowest
•
•
Factors affecting EN value
Size of atom/distance – small size/distance – stronger attraction for electron
Nuclear charge – higher nuclear charge – stronger attraction for electron
Nuclear charge
EN increase across period 2
Li
+3
Be
+4
B
+5
C
+6
N
+7
O
+8
F
+9
Period 2
EN increase across period 2
Nuclear charge increase
Strong attraction for electron
EN increase
Electronegativity
EN increase up a Group
EN increase across a Period
37. Electronegativity
Electronegativity (EN)
Tendency of atom to attract/pull shared/bonding electron to itself
EN value higher – pull/attract electron higher (EN value from 0.7 – 4)
•
•
Shared electron cloud closer to O
•
•
EN highest
EN lowest
•
•
Electronegativity
EN increase up a Group
EN increase across a Period
Factors affecting EN value
Size of atom/distance – small size/distance – stronger attraction for electron
Nuclear charge – higher nuclear charge – stronger attraction for electron
Size
Gp 17
EN decrease down gp 17
F
Size increase
Nuclear charge
CI
Attraction electron decrease
EN increase across period 2
EN lower
Li
+3
Br
Be
+4
B
+5
C
+6
N
+7
O
+8
F
+9
Period 2
I
EN increase across period 2
Nuclear charge increase
Strong attraction for electron
EN increase
38. •
•
Melting point across Period 2/3
Melting point down Gp 1/17
Melting Point
•
•
Temp when solid turn to liquid (temp remain constant)
Energy absorb to overcome forces attraction bet molecule
Period 2/3
Gp 1
Melting Point
Gp 17
Factors affecting melting point
Type of bonding/forces
Structure
Metallic/Non Metallic
structure
Covalent
structure
Simple molecular
structure
Ionic
structure
Giant molecular
structure
Metallic Bonding
Covalent Bonding
Ionic Bonding
39. •
•
Melting point across Period 2/3
Melting point down Gp 1/17
Melting Point
•
•
Temp when solid turn to liquid (temp remain constant)
Energy absorb to overcome forces attraction bet molecule
Period 2/3
Melting Point
Gp 1
Gp 17
Factors affecting melting point
Type of bonding/forces
Structure
Metallic/Non Metallic
structure
Covalent
structure
Simple molecular
structure
Ionic
structure
Metallic Bonding
Melting point across Period 2 and 3
Giant molecular
structure
period 2
C
period 3
B
Si
Be
Mg
Li
Na
N O F Ne
AI
P S
Covalent Bonding
CI
Ionic Bonding
40. Melting point for metallic/non metallic
C
Melting Point
Melting point across Period 2
period 2
B
Be
Li
N O F Ne
41. Melting point for metallic/non metallic
Melting point across Period 2
Melting Point
C
period 2
B
Be
Li
N O F Ne
Li
Be
B
C
N
O
F
Ne
m/p
(/C)
180
1280
2300
3730
-210
-218
-220
-249
structure
metallic
metallic
Giant
covalent
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
Mono
atomic
bonding
metallic
metallic
Giant
covalent
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Simple
covalent
•
•
•
Across period 2
m/p increase from Li – C
m/p drop from N – Ne
Metallic – non metallic
42. Melting point for metallic/non metallic
Melting point across Period 2
Melting Point
C
period 2
B
Be
Li
N O F Ne
Li
Be
B
C
N
O
F
Ne
m/p
(/C)
180
1280
2300
3730
-210
-218
-220
-249
structure
metallic
metallic
Giant
covalent
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
Mono
atomic
bonding
metallic
metallic
Giant
covalent
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Metallic bonding
Strong attraction bet
nucleus with sea of electrons
High m/p
•
•
•
Across period 2
m/p increase from Li – C
m/p drop from N – Ne
Metallic – non metallic
43. Melting point for metallic/non metallic
Melting point across Period 2
Melting Point
C
period 2
B
Be
Li
N O F Ne
Li
Be
B
C
N
O
F
Ne
m/p
(/C)
180
1280
2300
3730
-210
-218
-220
-249
structure
metallic
metallic
Giant
covalent
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
Mono
atomic
bonding
metallic
metallic
Giant
covalent
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Metallic bonding
Giant covalent
Strong attraction bet
nucleus with sea of electrons
Macromolecular structure with
strong covalent bonds
High m/p
Highest m/p
•
•
•
Across period 2
m/p increase from Li – C
m/p drop from N – Ne
Metallic – non metallic
44. Melting point for metallic/non metallic
Melting point across Period 2
Melting Point
C
period 2
B
Be
Li
N O F Ne
Li
Be
B
C
N
O
F
Ne
m/p
(/C)
180
1280
2300
3730
-210
-218
-220
-249
structure
metallic
metallic
Giant
covalent
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
metallic
metallic
Giant
covalent
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Across period 2
m/p increase from Li – C
m/p drop from N – Ne
Metallic – non metallic
Mono
atomic
bonding
•
•
•
Simple
covalent
Metallic bonding
Giant covalent
Simple covalent
Van der waals forces bet molecules
Strong attraction bet
nucleus with sea of electrons
Macromolecular structure with
strong covalent bonds
High m/p
Highest m/p
Simple molecular weak Van Der Waals
forces attraction bet molecules
Low m/p
45. Melting point for metallic/non metallic
Melting Point
Melting point across Period 3
Period 3
Si
Mg AI
Na
P S
CI Ar
46. Melting point for metallic/non metallic
Melting point across Period 3
Melting Point
Period 3
Si
Mg AI
Na
Na
Mg
P S
AI
CI Ar
Si
P
S
CI
Ar
m/p
(/C)
98
650
660
1423
44
120
-101
-189
structure
metallic
metallic
metallic
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
Mono
atomic
bonding
metallic
metallic
metallic
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Simple
covalent
•
•
•
Across period 3
m/p increase from Na – Si
m/p drop from P – Ar
Metallic – non metallic
47. Melting point for metallic/non metallic
Melting point across Period 3
Melting Point
Period 3
Si
Mg AI
Na
Na
P S
Mg
AI
CI Ar
Si
P
S
CI
Ar
m/p
(/C)
98
650
660
1423
44
120
-101
-189
structure
metallic
metallic
metallic
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
Mono
atomic
bonding
metallic
metallic
metallic
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Metallic bonding
Strong attraction bet nucleus
with sea of electrons
High m/p
•
•
•
Across period 3
m/p increase from Na – Si
m/p drop from P – Ar
Metallic – non metallic
48. Melting point for metallic/non metallic
Melting point across Period 3
Melting Point
Period 3
Si
Mg AI
Na
Na
P S
Mg
CI Ar
AI
Si
P
S
CI
Ar
m/p
(/C)
98
650
660
1423
44
120
-101
-189
structure
metallic
metallic
metallic
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
Mono
atomic
bonding
metallic
metallic
metallic
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Metallic bonding
Giant covalent
Strong attraction bet nucleus
with sea of electrons
Macromolecular structure
with strong covalent bonds
High m/p
Highest m/p
•
•
•
Across period 3
m/p increase from Na – Si
m/p drop from P – Ar
Metallic – non metallic
49. Melting point for metallic/non metallic
Melting point across Period 3
Melting Point
Period 3
Si
Mg AI
Na
Na
P S
Mg
CI Ar
AI
Si
P
S
CI
Ar
m/p
(/C)
98
650
660
1423
44
120
-101
-189
structure
metallic
metallic
metallic
Giant
covalent
Simple
molecular
Simple
molecular
Simple
molecular
metallic
metallic
metallic
Giant
covalent
Simple
covalent
Simple
covalent
Simple
covalent
Across period 3
m/p increase from Na – Si
m/p drop from P – Ar
Metallic – non metallic
Mono
atomic
bonding
•
•
•
Simple
covalent
Metallic bonding
Giant covalent
Simple covalent
Van der waals forces between molecules
Strong attraction bet nucleus
with sea of electrons
Macromolecular structure
with strong covalent bonds
High m/p
Highest m/p
Simple molecular weak Van Der Waals
forces attraction bet molecules
Low m/p
50. Atomic Radius- Group 1 and 17
Ionization Energy – Group 1 and 17
Atomic Radius
Atomic Radius
Atomic Radius
Gp 1
shell
Melting point – Group 1 and 17
Atomic Radius
Ionization Energy
Gp 17
shell
Melting point
Gp 1
Gp 17
Gp 1
Gp 17
Li
F
Li
2.1
F
2.7
Li
F
Na
2.8.1
CI
2.8.7
Na
CI
Na
CI
K
2.8.8.1
2.8.18.7
K
Br
K
Br
Rb
I
Rb
2.8.8.18.1
Br
2.8.18.18.7
I
Why atomic radius increase ?
Number shell increase
Valence e further away from nucleus
Atomic radius High
Rb
I
IE decrease down group
Number shell/energy level increase
Valence e further away from nucleus
Weak forces attraction bet nucleus and e
IE – Low
m/p down Gp 1
Size increase
Attraction bet nucleus and
sea electrons decrease
Metallic bonding
Melting point
m/p increase Gp 17
Size increase
VDF increase
IMF attraction bet
molecules increase
Melting point
51. Acknowledgements
Thanks to source of pictures and video used in this presentation
http://crescentok.com/staff/jaskew/isr/tigerchem/econfig/electron4.htm
http://pureinfotech.com/wp-content/uploads/2012/09/periodicTable_20120926101018.png
http://chemglobe.org/ptoe/
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