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chlorine dioxide carbon monoxidedinitrogen pentaoxide phosphorus pentachloride
silicon monocarbide sulfur hexafluoridedisulfur dichloride silicon tetrachloridesilicon dioxide chlorine trifluoridetetraphosphorus decaoxidesulfur dioxidedioxygen difluoridenitrogen trichloridediboron trioxidediarsenic trisulfide
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chlorine monoxide oxygen difluorideberyllium oxide carbon tetrachloridephosphorus triiodide potassium permanganate
zinc oxide trisilicon tetranitridenitrogen dioxide phosphorus pentabromide
nitrogen dinitrogen monoxidetin(IV) cyanidedichlorine monoxidenitrogen trifluoridedichlorine octaoxidesulfur trioxide
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TODAY: read page 37 and pages 164-167
Diatomic moleculesLewis Dot Diagrams for MoleculesHW: Worksheet – Lewis Structure
exercisesRetest: Monday Feb. 4Quiz: Thursday or Fri Feb. 7 or 8
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ELECTRONEGATIVITYAND POLARITY
• electronegativity = ability of an atom to attract electrons in a covalent bond
• most electroneg. element = flourine• least electroneg. element = francium• Unequal sharing of electrons will produce
a polar bond.
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ELECTRONEGATIVITYAND POLARITY
• F–F• H–F• H2O
• NH3
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diatomic molecules: molecules with 2 atoms of the same element there are 7 – know them!
N2 O2 H2 Cl2 I2 F2 Br2
orBr2 I2 N2 Cl2 H2 O2 F2
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show the valence electrons as dots
inner electrons and atomic nuclei are represented by the symbol
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group 1A: 1 valence e-
group 2A: 2 valence e-, etc.
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diatomic molecules
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1. Count valence electrons and bonds using periodic table and octet rule – make a chart to get valence and shared electrons
2. Choose an arrangement of atoms (carbon in center, hydrogen or halogens on outside)
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3. Put in calculated number of bonds; single bonds first, then multiple bonds if necessary.
4. Where necessary to complete octets, put in non-bonding electrons in pairs.
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5. Check work by counting electrons in Lewis structure and comparing calculated number of valence electrons.
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LEWIS STRUCTURESCH2O
V SC 4 4H 1 1H 1 1O 6 2
12 8 / 2 = 4 bonds
lOH–C–H
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LEWIS STRUCTURESNH3
V SN 5 3H 1 1H 1 1H 1 1
8 6 / 2 = 3 bonds
H–N–H H
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LEWIS STRUCTURESSO3
2– V S
S 6 2O 6 2O 6 2O 6 2
24 8+2 -226 6 / 2 = 3 bonds
O–S–O O
2-
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POLYATOMIC IONSFROM NOW ON:know NO CO SO PO ions(–ates and –ites)know NH4
+
know –ides: cyanide, hydroxideknow chlorine containing ions