What is reactivity based on? What do all elements want to be happy? Draw the Lewis Dot Structure for Sodium and Chlorine.

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2 What is reactivity based on? What do all elements want to be happy? Draw the Lewis Dot Structure for Sodium and Chlorine.

3 FORCES What is a chemical bond? The force that holds two atoms together

4 Between different molecules Forces Within a compound (between elements) Intermolecular Forces Intramolecular Forces STRONGER Occurs in proteins When H bonds to N, O, F Nonmetal-Nonmetal Sharing of Metals Surrounding sea of Metal-Nonmetal Gain or loss of Unequal sharing of Equal sharing of

5 Intramolecular Force (stronger) holds elements together to make compounds Intermolecular Force (weaker) holds molecules together to form solids, liquids, and gases

6 Intramolecular Force The force within a compound between atoms. Example: the bond between O and H in a H 2 O molecule

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8 Example: the bond between Na and Cl in a NaCl molecules Na + Cl -

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10 Between different molecules Forces Within a compound (between elements) Intermolecular Forces Intramolecular Forces STRONGER Occurs in proteins When H bonds to N, O, F Nonmetal-Nonmetal Sharing of Metals Surrounding sea of Metal-Nonmetal Gain or loss of Ionic Bond STRONGEST Covalent Bond Metallic Bond Unequal sharing of Equal sharing of

11 Ionic Bond (strongest) electrostatic attraction between a metal and nonmetal that involves a gain or loss of Covalent Bond between two nonmetals that involves a sharing of Metallic Bond between metal atoms and the surrounding sea of

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13 Ion- charged elements When an atom loses a valence electron to another atom, it becomes a (+) ion. This is a CA+ION. When an atom accepts a valence electron from another atom, it becomes a (-) ion. This is an ANION.

14 Between different molecules Intermolecular Forces Within a compound (between elements) Intramolecular Forces Occurs in proteins When H bonds to N, O, F Nonmetal-Nonmetal Sharing of Metals Surrounding sea of Metal-Nonmetal Gain or loss of Ionic Bond STRONGEST Covalent Bond Metallic Bond Cation Anion Unequal sharing of Equal sharing of

15 Between different molecules Forces Within a compound (between elements) Intermolecular Forces Intramolecular Forces STRONGER Occurs in proteins When H bonds to N, O, F Nonmetal-Nonmetal Sharing of Metals Surrounding sea of Metal-Nonmetal Gain or loss of Ionic Bond STRONGEST Covalent Bond Metallic Bond Unequal sharing of Equal sharing of

16 FULL OCTET

17 EXAMPLE Na Cl 7 valence e-

18 EXAMPLE 8 valence e- Na Cl Cation Na +1 Anion Cl -1

19 What is the difference between an intramolecular bond and intermolecular bond? What type of bond would form between Fluorine and Lithium? Why is Bromine more reactive than Aluminum?

20 Ca 2+

21 Ca 2+ S 2-

22 Shows the # of valence elecrons the atom has What is the charge on Ca? What is the charge on F? How many atoms of Ca and F are needed? DROP AND SWITCH THE CHARGES

23 Ca 2+ F -1 Drop Ca 2 F 1 Switch CaF 2

24 1+ 3- Drop Na 1 N 3 Switch Na 3 N

25 1. # of valence in aluminum? 3 2. Change in for octet? Lose 3 e - 3. Ionic charge of aluminum? Al 3+

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27 What type of bond will you have between Sodium and Nitrogen? What type of bond will you have between hydrogen and oxygen?

28 Sharing of H-H = H 2

29 Between different molecules Forces Within a compound (between elements) Intermolecular Forces Intramolecular Forces STRONGER Occurs in proteins When H bonds to N, O, F Nonmetal-Nonmetal Sharing of Metals Surrounding sea of Metal-Nonmetal Gain or loss of Ionic Bond STRONGEST Covalent Bond Metallic Bond Unequal sharing of Polar Nonpolar Equal sharing of

30 Polar Covalent Bond are unevenly shared; different EN values Nonpolar Covalent Bond are evenly shared; same or very close EN values

31 Electronegativity is the tendency of an atom to attract other atoms valence The more electronegative the atom, the stronger the attraction for Fluorine is the most electronegative atom on the periodic table

32 Fluorine the Flirt likes to attract other atoms valence Examples: H-F (polar) H-H (nonpolar)

33 The O atom pulls on the shared in each H causing a partial (+) charge on each H atom and partial ( ) charge on the O atom Why is O pulling the towards itself? O is more electronegative and attracts the unequal sharing of Why does water act like a magnet? Because the (+) attracts the (-)

34 Free floating among metals

35 Intermolecular Force The force between different molecules Example: an interstate highway runs between different states

36 Intramolecular Force Intermolecular Force

37 Intermolecular Force Intramolecular Force

38 Between different molecules Forces Within a compound (between elements) Intermolecular Forces Intramolecular Forces STRONGER Occurs in proteins When H bonds to N, O, F Disulfide Bonds Hydrogen Bond Nonmetal-Nonmetal Sharing of Metals Surrounding sea of Metal-Nonmetal Gain or loss of Ionic Bond STRONGEST Covalent Bond Metallic Bond Unequal sharing of Polar Nonpolar Equal sharing of

39 Hydrogen Bond when H bonds to N, O, or F o Important in DNA (genetic material), proteins, and water molecules Disulfide Bond occurs in proteins to ensure proper functioning and prevent destruction from extreme environments

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41 Single bond Share one pair of Double bond Share two pairs of

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43 Why do atoms form chemical bonds? How? To become more stable by losing, gaining, or sharing What does it mean when an atom is chemically unstable? It does not have a full octet of What does the octet rule state? The outermost energy level has 8 valence (full shell) What subatomic particle is involved in forming chemical bonds? Valence What is a molecule? Two or more elements chemically combined together How can the periodic table be used to determine the # of valence? Look at the group number (Transition Metals are different) How can the periodic table be used to determine the # of energy levels? Look at the period number Most matter is electrically neutral, why? The # of protons cancels out the # of