CHEMICAL BONDING WARM-UP

Answer the following questions INDEPENDENTLY!

A

B

C

D

E

Identify the shape:

Draw the following and predict the Shape of the Following:

(1) H2S

(2) CBr4

Identify the shape:

Draw the following and predict the Shape of the Following:

(1) H2S - Bent

(2) CBr4 -Tetrahedral

A) Bent

B) Trigonal Pyramidal

C) Linear

D) Trigonal Planar

E) Tetrahedral

CHECK YOUR ANSWERS and DISCUSS ANYTHING YOU MISSED:

HOMEWORK CHECKCheck your homework answers against the keys provided on the next two slides.

HOMEWORK REVIEW:

VSEPR THEORY PRACTICE WORKSHEET

TODAY’S OBJECTIVES

WHAT YOU WILL LEARN TODAY

Objectives

Identify bond strengths based upon type of bond.

Define polarity

Apply VSEPR theory to predict the overall polarity of a molecule.

Predict the properties of a molecule based on the type of molecule (Ionic, NPC, PC, Metallic)

IDENTIFY BOND STRENGTHS BASED UPON TYPE OF BOND

Bonds have lengths and strengths! Ionic bonds- Strongest of all bonds!

Covalent Bonds Triple Bonds – shortest and stronger Double bonds Single bonds - longest and weakest of all

the bonds.

Arrange the following in order of increasing bond strength.

CO2

CCl4SrBr2

N2

CHECK YOUR ANSWERS ON THE NEXT SLIDE

Arrange the following in order of increasing bond strength.

CCl4 – WEAKEST – SINGLE COVALENT

CO2 -- Double Covalent

N2 --- Triple Covalent

SrBr2 Ionic – STRONGEST!!

DEFINE POLARITY

DISCUSS WHAT THESE PICTURES

HAVE IN COMMON

What Does This Represent???(Think Electronegativity!!)

Polarity

Polarity is defined as the unequal distribution of electrons.

But what does that actually mean?

Polar molecules have a slightly positive end and a slightly negative end.

Nonpolar molecules have a consistent charge throughout and thus no charged poles (ends).

POLAR and NONPOLAR DO NOT MIX!!!!

POLAR BONDS create special properties due to small charges.

PUT THIS IN YOUR NOTES!!!!!

DEMO: BACK TABLE

On the back table is a test tube filled with the following….

Water, Oil, and Food Coloring

Which items are Polar and which are NON-Polar?

(Hint: Research to determine the polarity of water) Check Your Answers On The Next

Slide

DEMO: BACK TABLE

On the back table is a test tube filled with the following….

Water, Oil, and Food Coloring

Which items are Polar and which are NON-Polar?

Water and Food Coloring are BOTH POLAR as they mix together. The oil is NONPOLAR causing it to not mix with the water.

Check Your Answers On The Next Slide

APPLY VSEPR THEORY TO PREDICT THE OVERALL POLARITY OF A MOLECULE.

How do you know if a molecule is polar? COPY THIS INTO YOUR NOTES

Step 1: Draw Lewis Structure & Determine the shape

Step 2: Predict the polarity of the molecule based on the following. Bent, and trigonal pyramidal molecules are ALWAYS

polar. (think about WHY they are bent…lone pairs)

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 (NonPolar) vs. CH2F2 (Polar)

Examples – Work As A Team

Determine if the following molecules are polar or non-polar: NH3

CSeF2

CO2Check Answers On The Next Slide ---

Examples – Work As A Team

Determine if the following molecules are polar or non-polar: NH3 Polar

CSeF2 Polar

CO2 Non-Polar

You Try - Work Independently

Determine if the following molecules are polar or non-polar.

NF3

SO2

CH2I2

You Try - Work Independently

Determine if the following molecules are polar or non-polar.

NF3 POLAR

SO2 POLAR

CH2I2 POLAR

PREDICT THE PROPERTIES OF A MOLECULE BASED ON THE TYPE

(IONIC, NPC, PC, METALLIC)

Copy this chart and complete as you read the next few slides

Type of Bond

Conduct Electrici

ty

DissolveIn

water?

State at Room Temp

IONIC

METALLIC

POLAR

NON-POLAR

Properties of Ionic Substances Hard Brittle A solid at room temperature Very high melting points (≈800C) Very high boiling points Soluble in water (think SALT) 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 (does your gold necklace

wash away when you shower?)

Conduct electricity Malleable and ductile (think COPPER)

Properties of Polar Molecules

Typically a liquid at room temperature. Low melting points (≈20C) Medium boiling points Soluble in water (think SUGAR) 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 (think Oxygen) Not a conductor of electricity.

Here’s What You Should Have Learned

Type of Bond

Conduct Electricit

y

Dissolve

State at Room Temp

IONIC Y Y SolidMETALLIC Y N Solid

POLAR N Y Liquid

NON-POLAR N N Gas

Steps for determining properties.

Step 1: Draw the Lewis structures Step 2: Predict the shape Step 3: Based on the shape determine

the polarity Step 4: Use polarity to determine

properties

Given CO2

Work Together To Answer The Following Questions:

What is the overall shape? Using this shape, what type of bond is present?

Ionic, Metallic, Polar or Nonpolar? Given the shape, determine the following:

What is the state of matter at room temp? Will it conduct electricity Will it dissolve in water?

Check Your Answers On The Next Slide

Given CO2

Work Together To Answer The Following Questions:

What is the overall shape? Linear Using this shape, what type of bond is present?

Ionic, Metallic, Polar or Nonpolar? Nonpolar Given the shape, determine the following:

What is the state of matter at room temp? Gas Will it conduct electricity No Will it dissolve in water? No

PULLING IT ALL TOGETHER

Copy and complete the following table, working together as a team

Compound

Type of Bond?

(I, M, PC, PC)

Shape State of Matter

Conduct Electricity

?

Dissolve in Water?

CO2 NPC Linear Gas No No

PCl3

H2O

CCl4

MgCl2

Cl2

CH2Cl2

NH3

AlCl3

Compound

Type of Bond?

(I, M, PC, NPC)

Shape State of Matter

Conduct Electricity

?

Dissolve in Water?

CO2 NPC Linear Gas No No

PCl3 PC Trig Pyramidal

Liquid No Yes

H2O PC Bent Liquid No Yes

CCl4 NPC Tetrahedral Gas No No

MgCl2 Ionic Lattice Solid Yes Yes

Cl2 NPC Linear Gas No No

CH2Cl2 PC Tetrahedral Liquid No Yes

NH3 PC Trig Pyramidal

Liquid No Yes

AlCl3 Ionic Lattice Solid Yes Yes

YOU TRY IT -----

Compound

Type of Bond?

Shape State of Matter

Conduct Electricity

?

Dissolve in Water?

SrAt2

O3

SO3

HgZn -----

GeH2Br2

Type of Bond

Conduct Electricit

y

Dissolve State at Room Temp

IONIC Y Y Solid

METALLIC Y N Solid

POLAR N Y Liquid

NON-POLAR

N N GasWORK INDEPENDENTLY !!

YOU TRY IT -----

Compound

Type of Bond?

Shape State of Matter

Conduct Electricity

?

Dissolve in Water?

SrAt2 Ionic Lattice Solid Yes Yes

O3 PC Bent Liquid No Yes

SO3 NPC Trig Planar Gas No No

HgZn Metallic ----- Solid Yes No

GeH2Br2 PC Tetrahedral Liquid No Yes

Type of Bond

Conduct Electricit

y

Dissolve State at Room Temp

IONIC Y Y Solid

METALLIC Y N Solid

POLAR N Y Liquid

NON-POLAR

N N GasWORK INDEPENDENTLY !!

Objectives (Today You’ve Learned How To….)

Identify bond strengths based upon type of bond.

Define Polarity

Apply VSEPR theory to predict the overall polarity of a molecule.

Predict the properties of a molecule based on the type of molecule (Ionic, NPC, PC, Metallic)

HOMEWORK

BONDING WORKSHEET (WHOLISTIC VIEW)

HONORS…. OMIT INTERMOLECULAR FORCESSECTION UNTIL LATER

UNIT 4 QUIZ

When you’re finished, turn in paper and start on worksheet. Complete worksheet for homework!