Download Chem 222 Exam #1 Outline

Ch 222 Exam #1 Outline
Winter 2011
Ch 8 – Periodic Relationships Among the Elements
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Mendeleev and the Periodic Law
Representative elements, Noble gases, Transition elements, f-block transition elements
valence electrons – representative vs. transition metals
electron configurations of cations and anions (transition metals s-electrons removed first)
shielding and effective nuclear charge (nuclear charge effect)
periodicity in atomic radius, ionic radius, ionization energy, and electron affinity
Ch 9 – Chemical Bonding I: Basic Concepts
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Lewis dot symbols
Lewis structures for ionic compounds
Lattice energies, Coulomb's Law, and Born-Haber cycles
Lewis structures for covalent compounds, single, double, and triple bonds
Bond lengths
properties of covalent vs. ionic compounds
polar covalent compounds
trends in electronegativity
predicting polar covalent vs. ionic bonds
Lewis structures for charges species
formal charge
guidelines for drawing Lewis structures including (1) selecting a central atom with the lowest
electronegativity, (2) choosing a structure with the least formal charge on each atom, (3)
choosing a structure where the lowest formal charge is on the most electronegative atom
drawing resonance structures (hybrids)
Exceptions to the Octet Rule: (1) less than 8 valence electrons for Group 3A, (2) expanded
octets when the central atom is in the 3rd period or higher (exccpt for charged polyatomic
ions mentioned in the major exception above), (3) odd-electron species (free radicals)
bond energies and calculation of Horxn
Ch10 on the back 
Ch 10 – Chemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals
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VSEPR Geometry (A = central atom, B = terminal atom, E = lone pair)
Electron Cloud
Geometry
Linear
Trigonal planar
Tetrahedral
Trigonal Bipyramidal
NOTE: lone pairs are
equatorial
Octahedral
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Bond Angles
180o
120o
109.5o
equatorial =
120o, apical =
90o to the
equatorial plane
90o
Molecular Geometry
Linear (AB2)
Trigonal Planar (AB3)
Bent (AB2E)
Tetrahedral (AB4)
Trigonal Pyramidal (AB3E)
Bent (AB2E2)
Trigonal Bipyramidal (AB5)
Distorted Tetrahedron or “seesaw”
(AB4E)
T-shaped (AB3E2)
Linear (AB2E3)
Octahedral (AB6)
Square Pyramidal (AB5E)
Square Planar (AB4E2)
Applying VSEPR theory - (1) Lewis structure, (2) count electron clouds around central atom,
(3) determine appropriate VSEPR electron cloud geometry first, (4) then determine
molecular geometry based on the position of atoms in space
Remember: Multiple bonds count as one cloud in VSEPR theory
Molecular geometries of more complicated molecules with more than one central atom
(apply VSEPR theory to each central atom)