LecturePLUS Timberlake1 Chapter 2 Chemical Bonds Covalent Bonds Ionic Bonds Hydrogen Bonds

LecturePLUS Timberlake2 Chemical Bonds A force that joins atoms is called a chemical bond. Atoms form bonds to become stable which means they want to have a full outer shell.

LecturePLUS Timberlake3 Chemical Compound A compound is a substance made of the joined atoms of two or more different elements. Examples: H 2 O, CO 2, C 6 H 12 O 6, NaCl

LecturePLUS Timberlake4 Types of Bonds: Covalent Bonds - Example: Bonds in C 6 H 12 O 6 Ionic Bonds - Example: Bonds in NaCl Hydrogen Bonds - Example: Bonds b/w H 2 O

LecturePLUS Timberlake5 Covalent Bonds: Covalent bonds form when two or more atoms share electrons to form a molecule. The more electrons in the covalent bond, the more strongly the 2 atoms are joined. Types: –Single bond – share 2 electrons. –Double bond – share 4 electrons. –Triple bond – share 6 electrons.

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7 Molecules

LecturePLUS Timberlake8 Ionic Bonds Atoms on the left side of the periodic table tend to give up or lose electrons. Atoms on the right side of the periodic table tend to accept or gain electrons. When an atom loses or gains one or more electrons, the result is an ion. –Negative ion = gained 1 or more electrons. –Positive ion = lost 1 or more electrons. The strong attraction between oppositely charged ions is called an ionic bond.

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10 Hydrogen Bonds (Water) Shared electrons are attracted more strongly by the oxygen nucleus than by the hydrogen nuclei. This creates a partial positive end and partial negative end. This unequal distribution of electrical charge is called polarity

LecturePLUS Timberlake11 Hydrogen Bonds Water molecules are attracted to each other by hydrogen bonds.