Organic Chemistry Chp 4 Flashcards
Pauli Exclusion Principle
each orbital accommodates 2 e- that have the opposite spin
Hunds Rule
In degenerate orbitals, one e- is placed in each degenerate orbital before e- pair up.
When 2 ____ orbitals overlap, they are replaced by 2 ___ orbitals that are associated with the entire molecule
When 2 Atomic orbitals overlap, they are replaced by 2 MOLECULAR orbitals that are associated with the entire molecule
out of bonding Mos and Antibonding Mos, which ones have higher energy
Bonding Mo’s are lower energy and are thus more stable.
Antibonding Mo’s result in higher energy molecular orbitals.
______ interference results in _____ molecular orbits
DESTRUCTIVE interference results in ANTIBONDING molecular orbits
degenerate orbitals
orbitals with the same energy level but different nodes.
how many degenerate orbitals are in the p orbital?
3 (they are all energetically equivalent)
methane is sp__ hybridized
sp3
what kind of bond results from p orbitals overlapping?
pi orbitals
What kind of bond results from sp2 hybridized orbitals overlapping?
sigma bonds
what kind of bonds make up a double bond?
1 pi bond, and 1 sigma bond
two things that a compound must not have if it is saturated
1) no pi bonds
2) no rings
what is the hybridization of a carbocation
sp2 hybridized
a molecule that is more stable will be ____ reactive
less
A molecule’s stability is _____ related to its reactivity
inversely related to its reactivity
2 major ways for organic intermediates to be stabilized
1) inductive effects
2) resonance effects
electron-donating groups tent to stabilize _______ intermediates
electron deficient intermediates.
why is trichloric acid a better acid than acetic acid? think of methods of stabilization
the trichloric acid is a better acid due to its inductive effects. The chlorines withdraw electrons from the carbon center, making it easier for the -OH group to deprotonate. Essentially, the chlorines “destabilize” the molecule so that it can deprotonate into it’s conjugate base.
it is a better acid than acetic acid because the CH3 groups of acetic acid do not withdraw electrons as intensely as trichloric acid’s chlorines
which type of bonds does induction work through?
only sigma bonds. a double bond does not allow inductive effects. ex/ a ketone oxygen will not contribute to inductive effects of a molecule
All the carbons in benzene are ____ hybridized, meaning they have an unhybridized p orbital.
sp2 hybridized. They all have resonance
bond angle associated with sp, sp3 and sp2 hybridization
sp= 180 degrees
sp3= 109
sp2=120
3 criteria for resonance structure stability
1) a resonance structure is more stable if more atoms in the molecule fulfill their octet rule
2) a resonance structure has increased stability if there is a minimized separation of charge and if there are not multiple formal charges on the same molcule
3) a resonance structure has increased stability if the negative charges are placed on an electronegative atom rather than a less electronegative atom
A nitro group substituent on a phenol ring in para position will ____ acidity
increase acidity, it is electron withdrawaing and will draw electrons away from the acidic hydrogen
a methoxyphenol group substituent on a phenol ring in para position will ____ acidity
decrease acidity. It is electron donating and will destabilize the conjugate base when the molecule is deprotonated because it does not contribute to resonance effects
nucleophiles typically take on what type of charge?
negative
electrophiles typically take on what type of charge?
positive
nucleophiles are also known as
lewis bases
how does electronegativity play a role in nucleophilicity?
the LESS electronegative an atom is, the HIGHER the nucleophilicity. It wants positive charges more than an En atom
the ___ electronegative an atom is, the _____ the nucleophilicity
the LESS electronegative an atom is, the HIGHER the nucleophilicity. It wants positive charges more than an En atom
an electrophile is also known as a lewis ___
acid
what happens when an electrophile accepts electrons from a nucleophile?
they form a covalent bond between each other
