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The Nature of Covalent Bonding. 9.1. The colors in this map indicate the concentrations of ozone in various parts of Earth’s atmosphere. Oxygen atoms can join in pairs to form the oxygen you breathe and can also join in groups of three oxygen atoms to form ozone. 8.2.
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The Nature of Covalent Bonding 9.1 • The colors in this map indicate the concentrations of ozone in various parts of Earth’s atmosphere. Oxygen atoms can join in pairs to form the oxygen you breathe and can also join in groups of three oxygen atoms to form ozone.
8.2 The Octet Rule in Covalent Bonding • The Octet Rule in Covalent Bonding • What is the result of electron sharing in covalent bonds?
8.2 The Octet Rule in Covalent Bonding • In covalent bonds, electron sharing usually occurs so that atoms attain the electron configurations of noble gases.
8.2 Single Covalent Bonds • Single Covalent Bonds • How do electron dot structures represent shared electrons?
8.2 Single Covalent Bonds • Two atoms held together by sharing a pair of electrons are joined by a single covalent bond.
8.2 Single Covalent Bonds • An electron dot structure such as H:H represents the shared pair of electrons of the covalent bond by two dots.
8.2 Single Covalent Bonds • The halogens form single covalent bonds in their diatomic molecules. Fluorine is one example.
8.2 Single Covalent Bonds • A pair of valence electrons that is not shared between atoms is called an unshared pair, also known as a lone pair or a nonbonding pair.
8.2 Single Covalent Bonds • The hydrogen and oxygen atoms attain noble-gas configurations by sharing electrons.
8.2 Single Covalent Bonds • The ammonia molecule has one unshared pair of electrons.
8.2 Single Covalent Bonds • Methane has no unshared pairs of electrons.
8.1 Section Assessment
8.1 Section Assessment
for Conceptual Problem 8.1 Section Assessment Problem Solving 8.8 Solve Problem 8 with the help of an interactive guided tutorial.
8.2 Double and Triple Covalent Bonds • Double and Triple Covalent Bonds • How do atoms form double or triple covalent bonds?
8.2 Double and Triple Covalent Bonds • Atoms form double or triple covalent bonds if they can attain a noble gas structure by sharing two pairs or three pairs of electrons.
8.2 Double and Triple Covalent Bonds • A bond that involves two shared pairs of electrons is a double covalent bond. • A bond formed by sharing three pairs of electrons is a triple covalent bond.
Covalent Bonds • Simulation 6 Simulate the covalent bonding between molecules
8.2 Double and Triple Covalent Bonds • Each nitrogen atom has one unshared pair of electrons.
8.2 Double and Triple Covalent Bonds
8.2 Double and Triple Covalent Bonds • Carbon dioxide gas is soluble in water and is used to carbonate many beverages. A carbon dioxide molecule has two carbon-oxygen double bonds.
8.2 Double and Triple Covalent Bonds • Carbon dioxide is an example of a triatomic molecule.
8.2 Coordinate Covalent Bonds • Coordinate Covalent Bonds • How are coordinate covalent bonds different from other covalent bonds?
8.2 Coordinate Covalent Bonds • In carbon monoxide, oxygen has a stable configuration but the carbon does not.
8.2 Coordinate Covalent Bonds • As shown below, the dilemma is solved if the oxygen donates one of its unshared pairs of electrons for bonding.
8.2 Coordinate Covalent Bonds • In a coordinate covalent bond, the shared electron pair comes from one of the bonding atoms.
8.2 Coordinate Covalent Bonds • A polyatomic ion, such as NH4+, is a tightly bound group of atoms that has a positive or negative charge and behaves as a unit. • Most plants need nitrogen that is already combined in a compound to grow.
8.2 Coordinate Covalent Bonds
8.2 Section Assessment
8.2 Section Assessment
8.2 Section Assessment
for Conceptual Problem 8.2 Section Assessment Problem-Solving 8.10 Solve Problem 10 with the help of an interactive guided tutorial.
8.1 Molecules and Molecular Compounds • Molecules and Molecular Compounds • How are the melting points and boiling points of molecular compounds different from those of ionic compounds?
8.1 Molecules and Molecular Changes • Molecular compounds tend to have relatively lower melting and boiling points than ionic compounds.
8.1 Molecular Formulas • Molecular Formulas • What information does a molecular formula provide?
8.1 Molecular Formulas • A molecular formula is the chemical formula of a molecular compound. • A molecular formula shows how many atoms of each element a molecule contains.
8.1 Molecular Formulas • Formulas of Some Molecular Compounds
8.2 Section Quiz. • 8.2.
8.2 Section Quiz. • 1. In covalent bonding, atoms attain the configuration of noble gases by • losing electrons. • gaining electrons. • transferring electrons. • sharing electrons.
8.2 Section Quiz • 2. Electron dot diagrams are superior to molecular formulas in that they • show which electrons are shared. • indicate the number of each kind of atom in the molecule. • show the arrangement of atoms in the molecule. • are easier to write or draw.
8.2 Section Quiz • 3. Which of the following molecules would contain a bond formed when atoms share three pairs of electrons? • Se2 • As2 • Br2 • Te2
