ACS Organic Chemistry Final Exam (
Updated 2025 2026 ) 1 100 Complete
Questions & Answers (Solved) 100%
Correct Graded A+
Chapter 1 - Structure: Shape and stability
-Haworth Projections
-Common way to show cyclic molecules
-Up line --> Wedged
-Down line --> Dashed
Molecular orbital diagram
,1. fill the lowest energy orbital
2. no orbital may hold more than two electrons and they must
be of opposite spin
3. When filling degenerate orbitals (orbitals of the same
energy) each orbital receives one electron, then the degenerate
orbitals receive a second electron of the opposite spin
-AFTER hybridization - only one row (put one spin on each line
first then fill the others
-BEFORE hybridization - 2 or more rows (fill the lowest line
before moving to higher lines
-Look up atom in periodic table - column # = valence electrons
Molecular geometry
Dipole Moment
-A dipole moment arises when there is a difference in
electronegativity between two atoms in a bond, causing one
end of the bond to become partially negative (δ⁻) and the other
partially positive (δ⁺). This creates a polar bond.
-Less symmetry = stronger dipole
Dipole Moment Strength
1. The greater the difference in electronegativity between two
bonded atoms, the stronger the dipole moment.
2. Hydrogen bonding is strong
3. Does not cancel out is strongest, if something cancel out and
is left with a net dipole it is weaker than one that simply has a
net moment without cancelling anything out
, Resonance
-same molecular formula
-moves around charges and electrons NOT atoms
Biggest resonance contributor
1. All atoms obey the octet rule (especially for second-period
elements like C, N, O, F).
Atoms should not exceed or fall short of 8 electrons (unless it's
an exception like P or S).
2. Minimal formal charges.
The most stable structure has the fewest formal charges.
A neutral molecule is generally more stable than charged
forms.
3. If charges exist, they’re on appropriate atoms:
Negative charges should be on more electronegative
atoms (like O or N).
Positive charges should be on less electronegative atoms (like
C).
4. More covalent bonds (double bonds) = more stability, if the
octet rule is still satisfied.
A structure with more double or delocalized bonds tends to be
more stable if it doesn’t cause an octet violation.
5. Charge separation is minimized.
Updated 2025 2026 ) 1 100 Complete
Questions & Answers (Solved) 100%
Correct Graded A+
Chapter 1 - Structure: Shape and stability
-Haworth Projections
-Common way to show cyclic molecules
-Up line --> Wedged
-Down line --> Dashed
Molecular orbital diagram
,1. fill the lowest energy orbital
2. no orbital may hold more than two electrons and they must
be of opposite spin
3. When filling degenerate orbitals (orbitals of the same
energy) each orbital receives one electron, then the degenerate
orbitals receive a second electron of the opposite spin
-AFTER hybridization - only one row (put one spin on each line
first then fill the others
-BEFORE hybridization - 2 or more rows (fill the lowest line
before moving to higher lines
-Look up atom in periodic table - column # = valence electrons
Molecular geometry
Dipole Moment
-A dipole moment arises when there is a difference in
electronegativity between two atoms in a bond, causing one
end of the bond to become partially negative (δ⁻) and the other
partially positive (δ⁺). This creates a polar bond.
-Less symmetry = stronger dipole
Dipole Moment Strength
1. The greater the difference in electronegativity between two
bonded atoms, the stronger the dipole moment.
2. Hydrogen bonding is strong
3. Does not cancel out is strongest, if something cancel out and
is left with a net dipole it is weaker than one that simply has a
net moment without cancelling anything out
, Resonance
-same molecular formula
-moves around charges and electrons NOT atoms
Biggest resonance contributor
1. All atoms obey the octet rule (especially for second-period
elements like C, N, O, F).
Atoms should not exceed or fall short of 8 electrons (unless it's
an exception like P or S).
2. Minimal formal charges.
The most stable structure has the fewest formal charges.
A neutral molecule is generally more stable than charged
forms.
3. If charges exist, they’re on appropriate atoms:
Negative charges should be on more electronegative
atoms (like O or N).
Positive charges should be on less electronegative atoms (like
C).
4. More covalent bonds (double bonds) = more stability, if the
octet rule is still satisfied.
A structure with more double or delocalized bonds tends to be
more stable if it doesn’t cause an octet violation.
5. Charge separation is minimized.
