Do Now
When the bell rings
After the bell (2 min)
Answer:
In your seat:
What
is
as
light
as
a
1. With pen/pencil
feather, but even the
2. With Notebook
world’s strongest man or
3. With Handout
woman couldn’t hold it for
4. Ready for Do Now
more than a minute?
Agenda

 Do

Now (5 min)
Warm Up (10 min)
 Notes:
Intermolecular Forces
(20 min)
 Group
Practice (10 minutes)
 Independent
Practice(15 min)

Exit Slip (5 min)

Closeout (5 min)
Announcements
 All
quizzes are graded
 If
you missed the quiz, you need to makeup during office hours (or make a special
arrangement with me)
 Make-ups
must be completed by next Friday
(April 24th)
 There
are 6 grades in Q4 already, keep up
with any missing or make-up work
Unit: Gas Laws
Topic: Intermolecular
Forces
Objectives:
1.
2.
Compare and contrast ionic and covalent compounds
Explain how intermolecular forces affect a substances physical
phase
Guiding
Question
There
are
____________
molecules in a
piece of chalk.
What holds all
of the
molecules of
chalk together?
 There
Warm Up
are
____________
molecules in a piece
of chalk. What holds
all of the molecules
of chalk together?
 How many molecules
are in a piece of
chalk that has a mass
of 106g?
 How about 125g?
Vocabulary and Definitions
 Intermolecular
Force: forces of attraction
or repulsion which act between molecules.
They are weak compared to
intramolecular forces, the forces which
keep a molecule together.
 Polar:
a molecule with a positive region
and a negative region.
 Non-Polar:
a molecule without charges
KP #1: Holding
Matter
Together
 Matter
is held
together at two
levels
 Within
a molecule
(Bonds)
 Ionic
Bonds
 Covalent
Bonds
 Between
molecules
(Intermolecular
Forces)
 Hydrogen
 Van
bonding
der Waals forces
KP #2: Bonds
IONIC

Bond between a metal and a non-metal

Complete transfer of valence electrons

Example: LiF
KP #2: Bonds
COVALENT
 Bond
between two nonmetals
 Electrons are shared
 Example: H2O or CO2
(two categories: polar and nonpolar
covalent)
CFU Ionic or Covalent?
1.
2.
3.
NaCl
HCl
I2
4.
5.
6.
CO2
KBr
LiF
KP #3: Polar v. Non-Polar
Non-Polar
Polar

Molecules are polar bc….
1. Electrons are not shared
equally
2. Unequal distribution of
charges (one element is
more electronegative)
3. Not symmetrical
(asymmetrical)
4. Hydrogen bonds with
another non-metal

Except Group 4A

Molecules are non-polar bc…
1. Electrons are shared
equally
2. No permanent charges
(because it is being
equally pulled in all
directions)
3. Symmetrical
4. bond between 2 identical
nonmetals
H2, N2, F2,Cl2, Br2, I2, O2
KP #3: Check For Understanding
 Which
pair of atoms is held together
by a polar covalent bond?
a.
HCl
b.
MgCl2
c.
NaCl
d.
LiCl
KP #3: Check For Understanding
 What
type of molecule is H2O?
a.
Polar, with a symmetrical distribution of charge
b.
Polar, with an asymmetrical distribution of charge
c.
Nonpolar, with a symmetrical distribution of
charge
d.
Nonpolar, with an asymmetrical distribution of
charge
KP #3: Check For Understanding
 Circle
HF
the polar molecules
NaCl
CCl4
O2
HBr
KP #4:
Intermolecular
Forces
 All
material is held
together by attractive
forces, these are called
cohesive forces
 Hydrogen
 Van
Bonding
der Waals forces
 There
is always some
disruptive force that
can break it
 Motion
 Repulsion
of like charges
KP #4:
Intermolecular
Forces
Attractive
forces are
stronger
than
disruptive
forces
Attractive forces are equal
to disruptive forces
 The
balance of
attractive and
disruptive forces
determine the state of
matter
Disruptive
forces are
stronger
than
attractive
forces
KP #4:
Intermolecular
Forces
Van
der Waals
Forces
The
sum of all of
the attractive and
disruptive forces
between molecules
KP #4:
Intermolecular
Forces
Hydrogen
Bonding
The
attraction of a
polarized hydrogen
atom to a highly
electronegative
atom, such as
oxygen, nitrogen,
and fluorine.
Group Practice:
Book Page 396
#’s: 1, 2, 4
Independent Practice
What
How

C: 0 – 1, only on task conversation

H: Raise hand, move on to next
question until I am available

A: Completing questions

M: In clusters. 3 Hall passes.

P: Answering questions on reverse
side of notes, using notes, head
up, asking questions of partners
 10
minutes
 Complete
practice on
reverse side of notes
Exit Slip
How

C: 0 – 1, only on task
conversation

H: Raise hand, move on to
next question until I am
available

A: Completing exit slip

M: In clusters.

P: Answering exit slip
questions, answers on scrap
paper
What
Exit Slip
1.
Which of the following is not true concerning a covalent
compound?
a.
Bond between two non-metals
b.
Electrons are shared
c.
An example is AlCl3
d.
They can be polar or non-polar
Exit Slip
2.
3.
Which of the following would you expect to share electrons
unequally?
a.
I2
b.
CH3OH
c.
CH4
d.
O2
What type of molecule is HBr?
a.
Polar, with a symmetrical distribution of charge
b.
Polar, with an asymmetrical distribution of charge
c.
Nonpolar, with an symmetrical distribution of charge
d.
Nonpolar, with an asymmetrical distribution of charge