ORGANIC CHEMISTRY SMITH SEVENTH
EDITION PRACTICE TEST ALL CHAPTERS
2026 QUESTIONS ANSWERS GRADED A+
⩥Electron Donating and Withdrawing Groups.
Answer: o To determine if a group is electron donating or withdrawing:
1) Look at the first atom from the point of attachment. Compare its
electronegativity to the atoms bound to it. If it is more electronegative, it
will bear a partial negative charge and if it is less electronegative, it will
bear a partial positive charge.
2) Atoms with full or partial positive charges withdraw from whatever
they are attached to. Atoms with full or partial negative charges donate
to whatever they are attached to.
3) Hydrogen is considered neither electron donating nor withdrawing.
EDG increase the ability to react, by stabilizing the carbocation,
allowing for it react
EWG decrease the ability to react, by destabalizing the carbocation, it is
pulling the electron density away from the aromatic ring into itself, thus
making it less reactive.
,4) Alkenes are weakly electron withdrawing (just memorize this one)
⩥Electron donating Groups.
Answer: electron donating group (EDG) or electron releasing group
(ERG) is an atom or functional group that donates some of its electron
density into a conjugated π system via resonance or inductive effects,
thus making the π system more nucleophilic.
Alkyl groups are weak EDG
Amines are EDG
Alcohols are EDG
⩥Electron Withdrawing Groups.
Answer: An electron withdrawing group or EWG draws electrons away
from a reaction center. Makes it less nucleophilic
When this center is an electron rich carbanion or an alkoxide anion, the
presence of the electron-withdrawing substituent has a stabilizing effect
Nitro groups, cyano groups, sulphano groups, carbocylic acids, esters
(unless attached to Oxygen of an OR, then EDG), quanterary amines,
⩥SN1/SN2 and E1/E2.
,Answer: Review these patterns
SN1 competes with E1
SN2 competes with E2
SN1 does not compete with SN2 or E1 does not compete with E2
a 3' carbon must react via SN1 or E1 mechanism ALWAYS just on the
MCAT
⩥Acidity.
Answer: ALways look at the stability of the conjugate base
STability or lack thereof will be affected by EDG or EWG.
Alcohols are weaker acids than water due to donating effect of the R
groups
RESONANCE STABILIZATION, if there is resonance, it makes it more
acidic
⩥Bascity.
, Answer: EDG increases bascitity,
EWG decrease Bascitity
⩥Bascity vs. Nucleopohilicity.
Answer: Steric Hindrance favors bascitity over Nucleophilicity
- Nucleophiles must have VERY little hindrance,
-primary nucleophiles most common
-secondary atoms can often as as bases or nucleophiles
-tertirary atoms will only act as bases
Reactivity (low stability) favors bascicity over nucleophilicity
- if an atom has a full negative charge it will almost always act as a base
(halides are notable exceptions)
⩥Electrophilicity.
Answer: Electrophiles are always electron poor
they will ALWAYS have a full or partial positive charge
Always attacked by electron rnich species
EDITION PRACTICE TEST ALL CHAPTERS
2026 QUESTIONS ANSWERS GRADED A+
⩥Electron Donating and Withdrawing Groups.
Answer: o To determine if a group is electron donating or withdrawing:
1) Look at the first atom from the point of attachment. Compare its
electronegativity to the atoms bound to it. If it is more electronegative, it
will bear a partial negative charge and if it is less electronegative, it will
bear a partial positive charge.
2) Atoms with full or partial positive charges withdraw from whatever
they are attached to. Atoms with full or partial negative charges donate
to whatever they are attached to.
3) Hydrogen is considered neither electron donating nor withdrawing.
EDG increase the ability to react, by stabilizing the carbocation,
allowing for it react
EWG decrease the ability to react, by destabalizing the carbocation, it is
pulling the electron density away from the aromatic ring into itself, thus
making it less reactive.
,4) Alkenes are weakly electron withdrawing (just memorize this one)
⩥Electron donating Groups.
Answer: electron donating group (EDG) or electron releasing group
(ERG) is an atom or functional group that donates some of its electron
density into a conjugated π system via resonance or inductive effects,
thus making the π system more nucleophilic.
Alkyl groups are weak EDG
Amines are EDG
Alcohols are EDG
⩥Electron Withdrawing Groups.
Answer: An electron withdrawing group or EWG draws electrons away
from a reaction center. Makes it less nucleophilic
When this center is an electron rich carbanion or an alkoxide anion, the
presence of the electron-withdrawing substituent has a stabilizing effect
Nitro groups, cyano groups, sulphano groups, carbocylic acids, esters
(unless attached to Oxygen of an OR, then EDG), quanterary amines,
⩥SN1/SN2 and E1/E2.
,Answer: Review these patterns
SN1 competes with E1
SN2 competes with E2
SN1 does not compete with SN2 or E1 does not compete with E2
a 3' carbon must react via SN1 or E1 mechanism ALWAYS just on the
MCAT
⩥Acidity.
Answer: ALways look at the stability of the conjugate base
STability or lack thereof will be affected by EDG or EWG.
Alcohols are weaker acids than water due to donating effect of the R
groups
RESONANCE STABILIZATION, if there is resonance, it makes it more
acidic
⩥Bascity.
, Answer: EDG increases bascitity,
EWG decrease Bascitity
⩥Bascity vs. Nucleopohilicity.
Answer: Steric Hindrance favors bascitity over Nucleophilicity
- Nucleophiles must have VERY little hindrance,
-primary nucleophiles most common
-secondary atoms can often as as bases or nucleophiles
-tertirary atoms will only act as bases
Reactivity (low stability) favors bascicity over nucleophilicity
- if an atom has a full negative charge it will almost always act as a base
(halides are notable exceptions)
⩥Electrophilicity.
Answer: Electrophiles are always electron poor
they will ALWAYS have a full or partial positive charge
Always attacked by electron rnich species
