chemistry

Chapter 4 - Chemical Bonding
Outline
• 4.2 Naming Compounds and Writing
Formulas
• 4.1 Types of Chemical Bonds
• 4.4 Electronegativity, Unequal Sharing, and Polar Bonds
• 4.5 Vibrating Bonds and the Greenhouse Effect
• 4.3 Lewis Structures
• 4.6 Resonance
• 4.7 Formal Charge: Choosing among Lewis Structures
• 4.8 Exceptions to the Octet Rule
• 4.9 The Lengths and Strengths of Covalent Bonds
© 2014 W. W. Norton Co., Inc.

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Chemical Bonds
All chemical bonds consist of _______ that hold groups of atoms together and make them function as a unit.

A bond will form if the energy of the aggregate is ______than that of the separated atoms.
____________ – energy required to break a chemical bond

Bonding involves ________________.

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Chemical Bonds, cont.
In general, there are three types of chemical bonds:
I. Ionic bond: Transfer of electrons from one atom

to another. Seen primarily in M + NM. Bond is an electrostatic attraction of of a _______for an ______.
II. Covalent bond: Results from a ________ of

outermost electrons.
A. __________covalent: ______ sharing of electrons. Observed in two of the same NM’s or in C-H bonds.
B. ______covalent: ________ sharing of electrons.
Observed in two different NM’s (not C-H bonds)
III. Metallic bond: Chemical bond consisting of the

unequal

nuclei of metal atoms surrounded by a “____” of shared electrons detailed discussion to follow …

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Electronegativity and Types of Bonds
Q: Why do we see the different types of bonding?
A: Electronegativity difference.
Electronegativity (EN) is:
• The ability of an atom in a molecule to attract _________ in a bond to itself.
• Has values ranging from 4.0 for fluorine (the ______ electronegative) to 0.7 for cesium and francium (the
______ electronegative).
• The __________ in EN between two atoms determines what kind of bond will form:
Ionic, Nonpolar covalent, or Polar covalent
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Electronegativity Trends