Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
|
Incomplete Octet |
stable with fewer than 8 electrons in valence shell He (2), Li (2), Be (4), B (6) |
|
|
Expanded Octet |
Any element in period 3 and greater P (10), S (12), Cl (14) |
|
|
Odd numbers of electrons |
With odd number of valence electrons, cannot distribute those electrons to give eight to each atom; NO (11) |
|
|
Follow Always Oct |
C, N, O, F, Na, Mn |
|
|
Ionic Bonds |
Donate electrons Form lattice structures signifcant diff EN Cation/anion strong bonds: high mp/bp/dissolve aqueous/good conductors |
|
|
Covalent bond |
share electrons unequal sharing = polarity Coordinated covalent-both electrons from one energetically unfavorable to create ions weak bond=low mp/bp, poor conductors, do not dissociate in aqueous, |
|
|
Polar covalent bond |
diff in EN of .5-1.7 |
|
|
Dipole moment |
p=qd (Debye or columb-meter) p=dipole moment q=magnitude of the charge d=displacement vector of 2 charges |
|
|
Coordinate Covalent Bonds |
Lone pair attacks another atom with unhybridized p-orbital. helpful for keepint track of valence e- and formal charge Pay attention to in Lewis Acid/Base chem |
|
|
Drawing Lewis Dot Molecules |
Least EN is central Hydrogen and Halogen terminal Count all Valence electrons Draw single bonds btwn Use electrons to complete octets. Remaining go on central atom. If central has less than octet, use double/triple |
|
|
Formal Charge |
Perfect sharing Formal Charge = V-Nnb=1/2Nbonded V= normal # in valence shell N- electrons bonded/unbonded |
|
|
Resonance |
Represented with double headed arrows Different connectivity representing distribution of electrons. Draw a resonance hybrid- partial bonds More stable more input to hybrid |
|
|
Resonance Prefrence |
small or no formal charge less separation between charge negative formal charge on most EN atom |
|
|
vSEPR Theroy |
Predict molecular geometry using Lewis struct Look at bonding/nonbonding on central |
|
|
VSEPR shapes (MOLECULAR) |
Linear: 180 Trigonal Planar: 120 Tetrahedral: 109 Trigonal Bipyramidal: 90, 180, 120 Octahedral: 90, 180 Doesn't include LP |
|
|
Electronic Geometry |
Includes LP |
|
|
Net Dipole |
W/ symmetry, might have no net dipole, despite polarity of individual bonds. W/o symmetry, net dipole |
|
|
Atomic and Molecular Orbitals |
When bond, atomic orbitals of bonding elements interact to form molecular orbitals |
|
|
Bonding orbitals |
Overlap of two of the same sign orbitals |
|
|
Anti-bonding |
Overlap of two different sign orbitals |
|
|
Sigma bond |
head to head free rotation |
|
|
Pi bond |
no free rotation parallel electron cloud densities |
|
|
Intermolecular Forces |
London dispersion forces - weakest Dipole-dipole - intermediate Hydrogen - strong |
|
|
London Disperson |
short-lived dipole moments induce dipoles require close proximity depends on how easy to polarizemolecule Large molecules=easy probably not in gas |
|
|
Dipole-Dipole |
oppositely charged find eachother. energetically favorable. attractive electrostatic force btwn 2 molecules exist in solid/liquid but not gas polar=higher mp/bp. Different than london in Duration |
|
|
Hydrogen bonds |
strong form of dipole-dipoleNaked proton=hydrogen bound to (N,C,F)
impt to alcohols, amines, carboxylic acids high bp/mp |
