Mr. Kinton Honors Chemistry Bonding and VSEPR Mr. Kinton Honors Chemistry

Bonding Chemical Bond: atoms or ions that are strongly attached Ionic Bonds Covalent Bonds Metallic Bonds

Metallic Bonding Delocalized electrons that hold metals together Electrons have freedom to move Sea of electrons

Ionic Bonding Electrostatic forces that hold oppositely charged ions together Transfer of electrons Occur between a metal and a nonmetal

Polyatomic Ions Charged group of 2 or more atoms Memorize this list Table 2.4 and 2.5 (58-59) Positive and negative

Ionic Bond Properties Brittle substances High melting point Well defined 3-D arrangement

You Try! What are the charges that each element is likely to form? Sr Al Mg N

Covalent Bonding Sharing of electrons between 2 atoms Occurs between nonmetallic elements

Types of Covalent Bonds Bond Type Single Double Triple # of electrons 2 4 6 Notation — =  Bond Order 1 3 Bond Energy Lowest Middle Highest Bond Length Longest Shortest

You Try! Classify the following as Ionic or Covalent? MgH2 H2S OF2 FeF2 Mn2O3 Cl2F3

Bond Polarity and Electronegativity Definitions: Bond Polarity: description of the sharing of electrons Nonpolar covalent: bond where electrons are shared equally polar- covalent: one atom has a greater attraction for the electrons

Covalent Bonds Electronegativity Difference Type of Bond Nonpolar covalent Between 0.1 and 1.7 Polar Covalent Greater that 1.7 Ionic

Dipoles When 2 electrical charges are separated by a distance Dipole moment: quantitative measure of a molecules dipole Polar Molecule: molecule where the center of positive and negative charges are separate

Lewis Structures What is the purpose of a Lewis diagram? Lewis Structures visually show shared electrons Group 7A- 1 Covalent Group 6A- 2 Covalent Group 5A- 3 Covalent

You Try! How many bonds will the following atoms form? I S H P

Exceptions to the Octet Rule Odd Number of Electrons Ex) NO, ClO2, NO2 Less than an octet B and Be More than an octet Largest number of exceptions Ex) PCl5, SF4

Molecular Shapes Determined by the bond angles and bond lengths of a molecule Best explained by the general form of ABn A is our central atom Bn is the number of atoms bonded to A

Molecular Shapes There are 5 fundamental shapes of molecules

VSEPR Model Wait WHAT?! Valence-Shell Electron-Pair Repulsion Helps us determine the shape of a given molecule Electron Domain: Region where electrons occupy space Bonding Pair Nonbonding pair (lone pairs)

VSEPR Model Electrons are arranged to maximize distance Electron Domain Geometry: follows the ABn Molecular Geometry: Shows how the molecule exists in space