Aim: How do chemists use molecular geometry to predict polarity?

• Metallic bonding• Polarity of water and "hydrogen bonding“• Water

Aim: How do chemists use molecular geometry to predict polarity?

How to name covalent compounds?Use prefixes to note the number of each type of

atom: mono-, di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona-, deca-

Aim: How do chemists use molecular geometry to predict polarity?

• VSEPR (Valence Shell Electron Pair Repulsion) theory- a model that can be used to predict shape of a molecule based on repulsion of both bonding and nonbonding electron pairs.

• Challenge: Use VSEPR theory explain why carbon dioxide (CO2) has a linear shape while hydrogen sulfide (H2S) is bent.

Aim: How do chemists use molecular geometry to predict polarity?

• Describe the properties of ionic compounds, molecular substances, and metallic solids.

• Why do ionic compounds generally have higher melting and boiling points than molecular substances?

• Why are metals (with metallic bonds) good conductors of heat and electricity?

• Ionic compounds do not conduct electricity in the solid phase but do conduct electricity in the liquid phase or when dissolved. Explain.

Aim: How do chemists use molecular geometry to predict polarity?

Do Now: Draw the Lewis structure for water and describe its shape.

• Why is water polar?• Describe and draw/build four examples of polar

molecules.• Why is methane non-polar?• Describe and draw/build three examples of non-polar

molecules.• Challenge: Use VSEPR theory explain why carbon dioxide

(CO2) has a linear shape while hydrogen sulfide (H2S) is bent.