Warm Up

What are the three types of bonds?


Determine the type of bond, and how many of each
element are present in:
 Na2O

 CO2

 CuZn
Objectives

Draw the Lewis structures of ionic and covalent
structures.
Lewis Structures



Combining of the dot diagrams to show bonding
and to predict shape.
Every Element wants 8 electrons.
2 Types- covalent and ionic.
Ionic Lewis Structures



Step 1: Draw the Lewis dot diagrams for each
element.
Step 2: Draw an arrow from the metals electrons to
the empty spaces around the nonmetal.
Step 3: Redraw the Lewis dot diagrams showing the
movement of electrons AND charges.
Example


Draw the Lewis structure for:
NaCl
Example


Draw the Lewis structure for:
LiF
Example


Draw the Lewis structure for:
MgCl2
Example


Draw the Lewis structure for:
Na2O
You Try


Draw the Lewis structure for:
KI


BeI2


SrF2
Covalent Lewis Structures

Show the sharing of electrons.


Show bonds as


Show the lone pairs as
Steps for Lewis Structures
Step 1: Add up total number of valence electrons.
Step 2: Draw a skeleton by connecting each element
with a line. (Carbon or the solo element goes in the
middle)
★Hydrogen and the Halogens CANNOT be in
the center.
Step 3: Distribute the electrons as PAIRS. Start from
the outside and move inward.
Step 4: Check Ya Self! Count and adjust electrons till
each element has 8. (except Hydrogen)
Examples


Draw the lewis structures for the following:
CF4
Examples


Draw the lewis structures for the following:
H2O
Examples


Draw the lewis structures for the following:
PH3
Examples


Draw the lewis structures for the following:
O2
You Try


Draw the lewis structures for the following:
NH3


F2O


CO2
Warm Up


What elements and how many are present in:
CO2


PH3




MgBr2
Draw the Lewis structures for:
KCl


CaF2
Objectives


Draw the Lewis structures for covalent molecules
Predict the shape of a molecule given the formula.
Objectives


Distinguish between a polar and non-polar covalent
bond.
Draw Lewis structures of compounds.
Review

Ionic Bond
 Between

a metal and non-metal
Covalent Bond
 Between
a non-metal and another non-metal
 Two types: Polar and Non-polar covalent

Metallic Bond
 Between
a metal and a metal
Electronegativity




The attraction an element has to electrons.
Scale of 0-4
Can be used to determine the type of bond.
0-0.4 = Nonpolar covalent
0.41-1.7 = Polar Covalent
Greater than 1.7 is ionic
Example





Identify the following bonds as polar or non-polar
covalent:
H bonded to O
H bonded to C
C bonded to F
C bonded to N
Warm Up



What are the three types of bonds?
What is electronegativity?
Determine the type of bond in:
 Na2O
 CO2
 CuZn
Objectives


Determine the type and number of atoms in a
compound based on the formula.
Draw Lewis structures of ionic and covalent
compounds.
What is a Chemical Formula?

Tells you the elements in the compound.
 Notated

by the atomic symbol of the element.
Tells you the number of each element.
 Shown
by the subscript number. No number means 1.
 Note it is always a whole number!
Example


What type of elements and how many are in:
MgCl2
Example


What type of elements and how many are in:
NH3
Example


What type of elements and how many are in:
CF4
Example





Identify each element and amount of each element
in the following compounds:
H2O
CH4
NaCl
Li2O
Lewis Structures



Combining of the dot diagrams to show bonding
and to predict shape.
Every Element wants 8 electrons.
2 Types- covalent and ionic.
Ionic Lewis Structures



Step 1: Draw the lewis dot diagrams for each
element.
Step 2: Draw an arrow from the metals electrons to
the empty spaces around the nonmetal.
Step 3: Redraw the lewis dot diagrams showing the
movement of electrons AND charges.
Example


Draw the Lewis structure for:
NaCl
Example


Draw the Lewis structure for:
LiF
Example


Draw the Lewis structure for:
MgCl2
Example


Draw the Lewis structure for:
Na2O
You Try


Draw the Lewis structure for:
KI


BeI2


SrF2
Warm Up


What elements and how many are present in:
CO2


PH3




MgBr2
Draw the Lewis structures for:
KCl


CaF2
Objectives


Draw the Lewis structures for covalent molecules
Predict the shape of a molecule given the formula.
Steps for Lewis Structures
Step 1: Add up total number of valence electrons.
Step 2: Draw a skeleton by connecting each element
with a line. (Carbon, the solo element, or the most
electronegative element goes in the
middle)★Hydrogen and the Halogens CANNOT be in
the center.
Step 3: Distribute the electrons as PAIRS. Start from
the outside and move inward.
Step 4: Count and adjust electrons till each element
has 8. (except Hydrogen)
Examples


Draw the lewis structures for the following:
CF4
Examples


Draw the lewis structures for the following:
H2O
Examples


Draw the lewis structures for the following:
PH3
Examples


Draw the lewis structures for the following:
O2
You Try


Draw the lewis structures for the following:
NH3


F2O


CO2
Exit Card







Identify the type of bond as polar or non-polar:
CCl4
CH4
Identify the elements and their amounts of the
compounds above.
Draw the Lewis structures for:
NH3
CF4
Day 2
Warm Up


Classify the following bonds as ionic, polar covalent, or non-polar
covalent.
F2


MgI2




NH3
Draw the Lewis structures for the following:
F2


MgI2


NH3
Objectives

Predict the shape of a molecule based on the
VSEPR theory.
VSEPR







Stands for “Valence shell Electron pair Repulsion”
V-Valence
S-Shell
E-Electron
P-Pair
R-Repulsion
Basically Electrons don’t like each other very much!
Steps for predicting shapes



Step 1: Draw the Lewis structures for the compound
Step 2: Draw a box around the central
atom/element
Step 3: Predict the shape based on the following.
5 Shapes





Four single bonds-Tetrahedral
3 single bonds and 1 lone pair-Trigonal Pyramidal
2 single, 1 double-Trigonal planar
2 bonds (any type) and lone pairs-Bent
2 bonds no lone pairs OR just 2 atoms-Linear
Example


Predict the shape of the following:
SO3
Example


Predict the shape of the following:
H2O
Example


Predict the shape of the following:
NH3
You Try


Predict the shape of the following
PF3


MgCl2



SiO2
Exit Card






What does VSEPR stand for?
List the five different shapes of molecules.
Predict the shape of the following:
H2S
O3
CCl4
Warm Up




What does VSEPR stand for?
List the 6 different shapes of molecules.
Predict the shape of the following:
H2S


O3


CCl4
Objectives


Predict the polarity of a molecule based on the
structure of a molecule.
(Honors) Determine the intermolecular forces
between two molecules
Polar and nonpolar…again

Molecules have an overall polarity in addition to
polar and nonpolar bonds.
Polar molecules have unequal distribution of
electrons.
while
 Nonpolar molecules have an equal distribution of
electrons.

How do you know if a molecule is
polar?


First determine the shape of the molecule in
question.
Then Predict the polarity of the molecule based on
its shape.
 Bent,
and trigonal pyramidal molecules are ALWAYS
polar.
 Tetrahedral, trigonal planar, and linear are ALWAYS
nonpolar.
How do you know if a molecule is
polar?


Bent, and trigonal pyramidal molecules are
ALWAYS polar.
Tetrahedral, trigonal planar, and linear are usually
nonpolar. But can be polar, IF and ONLY IF there
are 3 or more different elements.
 Ex.
CH4 vs. CH2F2
Examples


Determine if the following molecules are polar or
non-polar.
SiBr4
Examples


Determine if the following molecules are polar or
non-polar.
OI2
Examples


Determine if the following molecules are polar or
non-polar.
O3
Examples


Determine if the following molecules are polar or
non-polar.
CO2
Examples


Determine if the following molecules are polar or
non-polar.
S3O
Examples


Determine if the following molecules are polar or
non-polar.
CSeF2
You Try


Determine if the following molecules are polar or
non-polar.
NF3


SO2


H2S
Warm Up


Determine if the following molecules are polar or
non-polar.
NF3


SiO2


H2S
Objectives


(Honors) Determine the intermolecular forces
between two molecules.
Predict the properties of a molecule or compound
May the Forces be with You

Intramolecular forces-




Intermolecular forces- the attractions between
molecules that account for properties such as
BP, MP, viscosity, surface tension, and solubility.
Types of Intermolecular Forces

Three types:
London Dispersion
Also called induced dipole
 Between non-polar molecules
 Very very weak

Dipole-Dipole
Between polar molecules
 Two oppositely charges ends.(one + and one -)

Hydrogen Bonding
NOT a bond.
 Between hydrogen of one molecule and
fluorine, oxygen, or nitrogen of ANOTHER
molecule.
 Extremely strong.

Ranking Intermolecular Forces


The stronger the IM the higher the Bp and Mp.
Hydrogen Bonds >>> Dipole >> London
Example
Rank the following in order of increasing
boiling point.
 PH3
 CH4
 CO2
 H2O

Example

Which will have a higher Mp? Why?

NH3 or PH3
Example

Water boils at 100C and H2S boils at -60C,
briefly explain why these two molecules have
vastly different boiling points despite having
similar structures and polarities.
You Try
Rank the following in order of increasing
boiling point.
 SBr2
 NH3
 SiO2

You Try
Rank the following in order of increasing
boiling point.
 F2O
 Cl2
 Br2O

Properties of Ionic Substances






Hard
Brittle
A solid at room temperature
Very very high melting and boiling Points
Soluble in water
Conduct electricity when dissolved in water or as a
liquid.
Properties of Metals






Shiny
Solid at room temperature.
Very high melting and high boiling points
Insoluble in water
Conduct electricity
Malleable and ductile
Properties of Polar Molecules




Typically a liquid at room temperature.
Low melting points and boiling points
Soluble in water
Not a of conductor electricity
Properties of Non-polar molecules




Typically a gas at room temperature.
Very low melting and boiling points
Insoluble in water
Not a conductor of electricity.
Steps for determining properties.




Step 1: Draw the Lewis structures of all compounds
involved.
Step 2: Predict the shape of all compounds
Step 3: Based on the shape determine the polarity
of the compound
Step 4: Once the polarity is determined look up the
properties for that type of compound.
Example


Which of the following will conduct electricity?
NaCl


CO2


ZnCu


H2O
Example


Which of the following will be a liquid at room
temperature?
NaCl


CO2


ZnCu


H2O
Example


Which of the following will be a gas at room
temperature?
NaCl


CO2


ZnCu


H2O
You Try


Predict the state of matter for each of the following
at room temperature.
MgBr2


O3


SO3


HgZn
Exit Card






Determine if the molecule is polar or non-polar and
predict the state of matter at room temperature:
NH3
HCl
O2
CHF3
OF2
Warm Up


Determine the probable state of matter at room
temperature for the following:
CS2


PH3


CBr4


H2O
Objectives

Predict the properties of the compounds based on
the type of molecule.
Examples


Predict the state of matter at room temperature of:
CO2


SrF2


PCl3
Exit Card






List one property of ionic compounds, metallic
compounds, polar compounds, and non-polar
compounds.
Predict the state of matter for the following at room
temperature.
H2O
NH3
Cu-Zn
BaO
Warm Up






What is the typical state of matter for:
Ionic substances
Polar compounds
Non-polar compounds
Which of the following would have the highest
boiling point? Lowest?
CO2, Na2O, H2O
Warm Up


Determine the polarity of:
SO3




H2S
Objectives



Predict the properties of a substance based on the
type of compound and its’ polarity.
(Honors) Describe the intermolecular forces present
in molecules.
(Honors) Rank molecules based on the
intermolecular forces involved.
Properties of Ionic Substances







Hard
Brittle
A solid at room temperature
Very high melting points (≈800C)
Very high boiling Points
Soluble in water
Conduct electricity when dissolved in water or as a
liquid.
Properties of Metals







Shiny
Solid at room temperature.
Very very high melting point (≈1000C)
Very Very high boiling point
Insoluble in water
Conduct electricity
Malleable and ductile
Properties of Polar Molecules





Typically a liquid at room temperature.
Low melting points (≈20C)
Medium boiling points
Soluble in water
Not a of conductor electricity
Properties of Non-polar molecules





Typically a gas at room temperature.
Very low melting (≈-100C)
Very low boiling points
Insoluble in water
Not a conductor of electricity.
How to Determine Properties




First: Draw the Lewis structures of all compounds
involved.
Next: Predict the shape of all compounds
Then: Based on the shape determine the polarity of
the compound
Finally: Once the polarity is determined look up the
properties for that type of compound.
Example


Which of the following will conduct electricity?
NaCl


CO2


ZnCu


H2O
Example


Which of the following will be a liquid at room
temperature?
NaCl


CO2


ZnCu


H2O
Example


Which of the following will be a gas at room
temperature?
NaCl


CO2


ZnCu


H2O
You Try


Predict the state of matter for each of the following
at room temperature.
MgBr2


O3


SO3


HgZn
Exit Card








Which of the following would dissolve in water:
NaCl
CH4
NH3
Rank the following in order of increasing boiling
point:
NH3
CO2
CSF2
Exit Card








Which of the following would dissolve in water:
NaCl
CH4
NH3
Rank the following in order of increasing boiling
point:
NH3
CO2
CSF2
Warm Up




Identify the type of compounds as ionic, covalent,
metalic:
CaS
BrF
Draw the Lewis Structure for AsI3, predict the shape,
determine its polarity, and predict its’ state of
matter at room temperature.