CHEM 334 EXAM 1 WISKUR QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED ANSWERS) ALREADY
GRADED A+
Conjugated Compound Ans✓✓✓A compound that has 2 or more
adjacent pi bonds separated by a single bond
If you think something is sp3 hybridized, what do you need to check
for? Ans✓✓✓If there is a p orbital in the atom adjacent that is able to
participate in resonance
Why are conjugated compounds more stable? Ans✓✓✓The pi systems
can interact via resonance, which results in more stable pi systems
Unconjugated Diene Ans✓✓✓No resonance between pi bonds because
they are separated by more than 1 single bond
Allene Ans✓✓✓Two double bonds on the same carbon (cummulated)
Which bond is shorter, an sp2-sp2 bond or an sp3-sp3 bond?
Ans✓✓✓sp2-sp2 bonds are shorter
Why are s-trans formations lower in energy than s-cis formations?
Ans✓✓✓Because of steric and torsional strain
, What is the relationship between energy and wavelength?
Ans✓✓✓Inversely proportional relationship
Explain HOMO & LUMO? Ans✓✓✓HOMO is your highest occupied
molecular orbital, and LUMO is your lowest unoccupied molecular
orbital, and their is a specific amount of energy it takes to jump from
HOMO to LUMO
If you have more conjugation, what happens to the HOMO and LUMO
energy gap? Ans✓✓✓It becomes smaller (it is easier to go from HOMO
to LUMO with more conjugation)
What is the color you see on objects? Ans✓✓✓The color/light that is
NOT absorbed
If you see white, what does this mean about absorption?
Ans✓✓✓Nothing is absorbed
If you see black, what does this mean about absorption? Ans✓✓✓All
the light is absorbed
If you see yellow, what light is absorbed? Ans✓✓✓Blue light
At what energy level do objects absorb light? Ans✓✓✓At the energy
level it takes to excite 1 electron from the HOMO to the LUMO
DETAILED ANSWERS (VERIFIED ANSWERS) ALREADY
GRADED A+
Conjugated Compound Ans✓✓✓A compound that has 2 or more
adjacent pi bonds separated by a single bond
If you think something is sp3 hybridized, what do you need to check
for? Ans✓✓✓If there is a p orbital in the atom adjacent that is able to
participate in resonance
Why are conjugated compounds more stable? Ans✓✓✓The pi systems
can interact via resonance, which results in more stable pi systems
Unconjugated Diene Ans✓✓✓No resonance between pi bonds because
they are separated by more than 1 single bond
Allene Ans✓✓✓Two double bonds on the same carbon (cummulated)
Which bond is shorter, an sp2-sp2 bond or an sp3-sp3 bond?
Ans✓✓✓sp2-sp2 bonds are shorter
Why are s-trans formations lower in energy than s-cis formations?
Ans✓✓✓Because of steric and torsional strain
, What is the relationship between energy and wavelength?
Ans✓✓✓Inversely proportional relationship
Explain HOMO & LUMO? Ans✓✓✓HOMO is your highest occupied
molecular orbital, and LUMO is your lowest unoccupied molecular
orbital, and their is a specific amount of energy it takes to jump from
HOMO to LUMO
If you have more conjugation, what happens to the HOMO and LUMO
energy gap? Ans✓✓✓It becomes smaller (it is easier to go from HOMO
to LUMO with more conjugation)
What is the color you see on objects? Ans✓✓✓The color/light that is
NOT absorbed
If you see white, what does this mean about absorption?
Ans✓✓✓Nothing is absorbed
If you see black, what does this mean about absorption? Ans✓✓✓All
the light is absorbed
If you see yellow, what light is absorbed? Ans✓✓✓Blue light
At what energy level do objects absorb light? Ans✓✓✓At the energy
level it takes to excite 1 electron from the HOMO to the LUMO
