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) H 2 S (2) CBr 4

Identify the shape: Draw the following and predict the Shape of the Following: (1) H 2 S - Bent (2) CBr 4 -Tetrahedral A)Bent B)Trigonal Pyramidal C) Linear D)Trigonal Planar E)Tetrahedral CHECK YOUR ANSWERS and DISCUSS ANYTHING YOU MISSED:

HOMEWORK CHECK Check 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. CO 2 CCl 4 SrBr 2 N 2 CHECK YOUR ANSWERS ON THE NEXT SLIDE 

Arrange the following in order of increasing bond strength. CCl 4 – WEAKEST – SINGLE COVALENT CO 2 -- Double Covalent N Triple Covalent SrBr 2 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. CH 4 (NonPolar) vs. CH 2 F 2 (Polar)

Examples – Work As A Team Determine if the following molecules are polar or non-polar:  NH 3  CSeF 2  CO 2 Check Answers On The Next Slide --- 

Examples – Work As A Team Determine if the following molecules are polar or non-polar:  NH 3 Polar  CSeF 2 Polar  CO 2 Non-Polar

You Try - Work Independently Determine if the following molecules are polar or non- polar.  NF 3  SO 2  CH 2 I 2

You Try - Work Independently Determine if the following molecules are polar or non- polar.  NF 3 POLAR  SO 2 POLAR  CH 2 I 2 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 Electricity Dissolve In 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 Electricity Dissolve State at Room Temp IONIC YYSolid METALLIC YNSolid POLAR NYLiquid NON- POLAR NNGas

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 CO 2 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 CO 2 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

CompoundType of Bond? (I, M, PC, PC) ShapeState of Matter Conduct Electricity? Dissolve in Water? CO 2 NPCLinearGasNo PCl 3 H2OH2O CCl 4 MgCl 2 Cl 2 CH 2 Cl 2 NH 3 AlCl 3

CompoundType of Bond? (I, M, PC, NPC) ShapeState of Matter Conduct Electricity? Dissolve in Water? CO 2 NPCLinearGasNo PCl 3 PCTrig PyramidalLiquidNoYes H2OH2OPCBentLiquidNoYes CCl 4 NPCTetrahedralGasNo MgCl 2 IonicLatticeSolidYes Cl 2 NPCLinearGasNo CH 2 Cl 2 PCTetrahedralLiquidNoYes NH 3 PCTrig PyramidalLiquidNoYes AlCl 3 IonicLatticeSolidYes

YOU TRY IT CompoundType of Bond? ShapeState of Matter Conduct Electricity? Dissolve in Water? SrAt 2 O3O3 SO 3 HgZn----- GeH 2 Br 2 Type of Bond Conduct Electricity DissolveState at Room Temp IONICYYSolid METALLICYNSolid POLARNYLiquid NON- POLAR NNGas WORK INDEPENDENTLY !!

YOU TRY IT CompoundType of Bond? ShapeState of Matter Conduct Electricity? Dissolve in Water? SrAt 2 IonicLatticeSolidYes O3O3 PCBentLiquidNoYes SO 3 NPCTrig PlanarGasNo HgZnMetallic-----SolidYesNo GeH 2 Br 2 PCTetrahedralLiquidNoYes Type of Bond Conduct Electricity DissolveState at Room Temp IONICYYSolid METALLICYNSolid POLARNYLiquid NON- POLAR NNGas WORK 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 FORCES SECTION UNTIL LATER

 UNIT 4 QUIZ  When you’re finished, turn in paper and start on worksheet. Complete worksheet for homework!