phy scie

1. Physical
Science
KIP AIZA F.
GABAWA,LPT,MAED-SCIE

4. CHECKING
OF
ATTENDANCE

5. LEARNING OBJECTIVES
1.Define electronegativity.
2.Find the electronegativity of elements in the periodic
table.
3.Explain the VSEPR Theory.
4.Draw the Geometry of molecules using VSPER
Theory.
5.Distinguish between polar and non-polar molecules.

10. Rule #2.When filling the sides of the
element symbol each side gets one dot
before doubling up. Exceptions are
Hydrogen & Helium.
Rule #1.No side can have more than two
dots because each orbital can only hold
two electrons.

12. ANSWER THIS!
MATCH THE
FOLLOWING ATOMS TO
THEIR
CORRESPONDING
LEWIS DOT
STRUCTURE. USE
YOUR PERIODIC TABLE
OF ELEMENTS FOR
YOU TO BE GUIDED.

23. TWO FACTORS THAT COULD DETERMINE
THE POLARITY OF MOLECULES
• The polarity of the
bonds between
atoms which can
be studied based
on
electronegativity
• The geometrical
shape of the
molecule which
can be predicted
via Valence Shell
Electron Pair
Repulsion Theory

25. Bond Polarity
Exists when two
bonded atoms
unequally share
electrons,
resulting in a
negative and a
positive end.

26. Electronegativity
The measure of the relative
tendency of an atom to attract
electrons to itself when
chemically combined with
another atom. The more
electronegativity the more it
tends to attract electron towards
itself.

27. Types of Polar Bonds
• Polar Covalent
• Occurs when electron pairs are unequally shared. The difference in
electronegativity between atoms is significant

28. examples of Polar Covalent Bonds
a.HCL
* EN of H = 2.1 EN of Cl = 3.0 ∆EN = 0.9
b. HF
* EN of H = 2.1 EN of F = 4.0 ∆EN = 1.9

29. Electronegativity and Bond Character
Electronegativity Difference Bond Character
> 2.1 Ionic
0.5 – 2.0 Polar covalent
0 – 0.4 Nonpolar covalent

30. Types of Polar Bonds
• Non - Polar Covalent
• Occurs when
electron pairs are
shared equally or the
difference in
electronegativity
between atoms is
less than 0.5.

31. examples of Non -Polar Covalent Bonds
a.H2 EN of H = 2.1 ∆EN = 0.0 , not a dipole
b.Cl2 EN of Cl = 3.0 ∆EN = 0.0, not a dipole
c.F2 EN of F = 4.0 ∆EN = 0.0, not a dipole

32. Electronegativity and Bond Character
Electronegativity Difference Bond Character
> 2.1 Ionic
0.5 – 2.0 Polar covalent
0 – 0.4 Nonpolar covalent

40. RECAP