Transcript Chemistry 100 - University of Illinois at Urbana–Champaign

To Do



7th HW assignment due Friday, April 10th by
10 pm.
Quiz #5 on Friday, April 10 in Discussion.
Continue reading Chapter 8 and doing the
suggested homework.
1
A Covalent Bond
2
Clicker Question
Imagine the bond formed in the carbon
monoxide molecule (C-O). Which atom would
you expect to have a greater attraction for the
electrons in the bond?
a) carbon
b) oxygen
c) They have the same attraction (both have n=2 as
highest energy level with an electron).
d) I do not know.
3
Electronegativity
4
5
Bond Types
6
Bond
Types
7
A Polar Bond
8
From the Periodic Table…
•
•
•
Electron configurations
Charges for ions in compounds (and thus
formulas for compounds)
Trends
•
•
•
•
Atomic radius
Ionization energy
Electronegativity
Polarity of Bonds
9
Clicker Question
The following chemical reaction releases heat:
A2 + B2  2AB. This means:
a)
b)
c)
d)
e)
more stable higher average bond energies
Reactants
Reactants
Reactants
Products
Products
Products
Products
Reactants
I do not know.
10
11
12
Lewis Structures
•
•
•
•
Determine the total number of valence
electrons in the molecule.
Form at least one bond between atoms in
the molecule (a pair of electrons is a
bond)
Arrange the rest of the electrons (in
pairs) to satisfy the octet rule or duet rule
(for hydrogen).
Watch for exceptions.
13