Final, General Flashcards
What period is the cutoff for not following the octet rule?
3 and beyond
What are some guidelines for finding the most stable resonance structure?
negative charge on most electronegative, no charge separation, all atoms up to second period have octet, more covalent bonds
What is the shape and bond angle for something with a steric number of 2?
Linear, 180
What is the shape and bond angle for something with a steric number of 3, none of which are lone pairs?
Trigonal Planar, 120
What is the shape and bond angle for something with a steric number of 3, one of which is a lone pair?
Bent, less than 120
What is the shape and bond angle for something with a steric number of 4, none of which is a lone pair?
Tetrahedral, 109
What is the shape and bond angle for something with a steric number of 4, one of which is a lone pair?
Trigonal pyramid, less than 109
What is the shape and bond angle for something with a steric number of 4, two of which are lone pairs?
Bent, much less than 109
What is the hybridization for something with a steric number of 2?
sp
What is the hybridization for something with a steric number of 3?
sp2
What is the hybridization for something with a steric number of 4?
sp3
How do intermolecular forces related to BP?
Stronger=higher
How does branching relate to BP?
Spherical/More branching = lower BP
Define bronsted/lowry acid and base.
Base is a proton acceptor and acid is proton donor
Define lewis acid and base.
Base is electron pair donor, acid is electron pair acceptor
Define nucleophile
An electron pair donor to an atom other than hydrogen, needs to have an overall negative charge or a delta negative charge
Define electrophile
An electron pair acceptor, needs to have an overall positive charge or a delta positive charge
Describe how the size of atom relates to the strength of acids
use when the atoms are from the same column, strength of acid increases as you go down and bond length increases
Describe how electronegativity relates to the strength of acids
use when atoms are from the same row, strength increases from left to right, as the bond weakens
Describe how hybridization relates to the strength of acids
use when the atom binding to the hydrogen is the same, strength increases with lower hybridization (sp3->sp2->sp) and weaker conjugate bases
Describe how solvents affect acid strength
acids are stronger in polar protic solvents
Describe a staggered conformation
substituents are completely out of line
Describe an anti conformation
a staggered conformation where the bulkiest groups are farthest apart
Describe an gauche conformation
a staggered conformation where the bulkiest groups are closest together
Describe an eclipse conformation
the substituents are directly behind each other
How do you determine cis or trans with a chair cyclohexane conformation?
Cis is pointing in the same direction, trans is pointing in different directions
Describe axial and equatorial positions on cyclohexane
Axial positions are vertical
Can start from headrest (pointing up) or footrest (down)
Alternate pointing up and down
The other ones are equatorial
Give the four conformations of cyclohexane in order of stability from most to least
Chair-> Twist-boat -> Boat -> Half-chair
Define isomer
compound with the same molecular formula
Define constitutional isomers
different atom connectivity
Define stereoisomers
different arrangement of the atoms in space
Define diastereomers
stereoisomers that are not mirror images (includes cis and trans)
Define enantiomers
stereoisomers that are non-superimposable mirror images, have opposite chirality on all chiral centers (check chirality with a one group swap, check superimposable with 180 rotation)
What is the difference between chiral molecules and achiral molecules?
Chiral lack a plane of symmetry
How do you determine the maximum number of stereoisomers?
2^n where n is the number of chiral centers
What are some examples of strong bases?
OH-, RO-, H-, NH2-, C-
What solvents do SN1 or E1 reactions prefer?
polar protic because they stabilize carbocations
What solvents do SN2 or E2 reactions prefer?
Polar aprotic, solvate cations
How is nucleophilicity determined in polar aprotic or polar protic solvents?
Nu follows basicity in polar aprotic, Nu follows level of solvation in polar protic (opposite)
How you you determine which products are formed in an E2 reaction?
Use more substituted double bond unless working with (CH3)3COK
Describe E and Z nomenclature
If the highest priority groups are on the same side, it is Z, different is E
Describe the energy change of bond formation or bond cleavage
Bond formation is exothermic, bond cleavage is endothermic
Define oxidation
loss of electrons or the uptake of O and/or the loss of H
Define reduction
the gaining of elections or the loss of O and/or the uptake of H
Describe organometallic compounds
Carbon-metal bond compounds, carbon has a negative charge, can be written as CM or C- and M+
