Unit#5ChemicalComposition参考模板范本.doc

1、Unit # 5: Chemical Composition(Chapters 7 and 8)I. “Intra-Chemical” BondingA. Definition: atoms (elements) held together by an _B. Types (3)1. Metallic: atoms of a metal _ the valence electrons because they _ 2. Ionic (strongest)a. Definition: electrons are _from one element to another (opposite cha

2、rges is attractive force)b. Called: _c. Atom that donates electron:(+) _ Atom that accepts electron:(-) _d. Oxidation State (number): e. Lewis Dot Formulas used to show outer shell electron transfer- Octet Rule: every element wants _ in its outer shell1. potassium + chlorine potassium chloride2. mag

3、nesium + fluorine magnesium fluoridef. Types of Ions1. Monatomic Cation: 2. Monatomic Anion: 3. Polyatomic Ions:AmmoniumNitrateChromateSulfateAcetateHydroxideChlorateCarbonatePhosphatePermanganateg. Writing Chemical Formulas1. 2. _of elements3. Writing chemical formulas (from the name)a) Recognize t

4、he (+) and (-) ionsb) Write the symbols of the elements with their charge* Note- a Roman Numeral will tell you what the charge is on the cation if there is more than one possibilityc) Adjust the number of each ion (with subscripts) as needed so the positive charge is equal and opposite the negative

5、charge.* Note if the ions are polyatomic and there is more than one, the ion is enclosed with parentheses with a subscript on the outside.* Examples:Sodium Chloride_Calcium Sulfate_Barium Phosphate_h. Naming Compounds1. Consists of _words:a) Name the cationb) Name the anionc) If the cation has more

6、than one possible charge, a Roman Numeral is used to show the charge.Ex: FeCl3Fe3+ Iron (III) Chloride FeCl2Fe2+ Iron (II) ChlorideEx: NH4Cl_ Cu2SO4_ NaC2H3O2_3. Covalent (_)a. Definition: valence electrons are _ between two elementsEx: F2 b. Types1. Polar Covalent (_): _ sharing of electrons one pu

7、lls more than the other the more electronegative element)2. Non-Polar Covalent (_): _ sharing of electronsc. Lewis Structures1. Examples (H2 and HCl)2. The number of covalent bonds formed by an atom equals the number of _electrons in the Lewis Dot Formula.3. Examplesa) waterb) ammoniac) methaned. Mu

8、ltiple Bonds1. Double bonds: _pairs of electrons are shared (Ex: O2- draw it) 2. Triple Bonds: _pairs of electrons are shared (Ex: N2 gas)e. Hybridization: combining of _ orbitals of nearly the same energy into new orbitals of equal energyEx. 1) C 1s22s22p2sp3 hybrid_ _ _ _ - _ _ _ _2s 2p acquires e

9、nergy 2s2p 2) B 1s22s22p1sp2 hybrid_ _ _ _ - _ _ _ _2s 2p acquires energy 2s2pf. Molecules with more than one element (polar vs. non-polar)1) Depends On: - Electronegativity difference (2 elements) - Non-bonded electron pairs (2+ elements) - Structure (symmetry) (2+ elements)g. Shapes of Molecules (

10、VSPER handout)h. Naming/Writing Formulas for Covalent Compounds1. _covalent compounds (2 elements)2. Formulas with two _3. Rulesa) First word:- prefix indicating the # of atoms for the first element (if there is more than one)- name of first elementb) Second word:- prefix for the number of atoms of

11、the second element- name of second elementII. “Inter-Chemical” BondingA. Definition: whole _attract and bond with one another.B. Types1. Hydrogen Bonding (medium strength):2. “VanderWaals” Forcesa. Dispersion (weakest): if not H-bonding or dipole-dipole, it must be dispersionb. Dipole-Dipole (strongest): between _molecules5 / 5