Worksheets10 - Reaction Mechanisms: Thermodynamic vs Kinetic Control
Total questions: 9
Worksheet time: 5mins
Name
Class
Date
1.
What primarily governs product composition under thermodynamic control?
a)
Relative rates of formation
b)
Product stability (equilibrium thermodynamics)
c)
Transition state energies
d)
Catalyst concentration
2.
What governs product composition under kinetic control?
a)
Relative rates of formation
b)
Product stability (equilibrium thermodynamics)
c)
Catalyst concentration
d)
Solvent polarity
3.
If ΔG‡A > ΔG‡B (activation energies), and the reaction is irreversible, which product will be the major product?
a)
Product A
b)
Product B
c)
Equal amounts of A and B
d)
Neither A nor B will form
4.
In the enolate formation example, what conditions favor the thermodynamic enolate?
a)
Weak base, protic solvent
b)
Strong, sterically hindered base, aprotic solvent
c)
High temperature
d)
Low temperature
5.
According to Hammond's Postulate, if two consecutive states in a reaction have similar energies, what is true about their structures?
a)
Their structures are vastly different
b)
Their interconversion involves significant reorganization
c)
Their interconversion involves only a small reorganization of molecular structure
d)
Their structures are identical
6.
In electrophilic aromatic substitution, the rate-determining step resembles which intermediate?
a)
The starting material
b)
The σ-complex (intermediate Ib)
c)
The final product
d)
None of the above
7.
What does the Curtin-Hammett principle primarily concern?
a)
The relative energies of starting materials
b)
The relative heights of energy barriers leading to products
c)
The equilibrium constant between reactants
d)
The concentration of the catalyst
8.
In the Curtin-Hammett scenario where B ⇌ A, and AG‡a > AG‡b, which product (Pa from A or Pb from B) will predominate?
a)
Pa
b)
Pb
c)
Equal amounts of Pa and Pb
d)
The product ratio is determined by the equilibrium constant K
9.
If |ΔG‡a - ΔG‡b| >> |ΔGa|, what primarily determines the product ratio [Pa]/[Pb]?
a)
ΔGa (the energy difference between A and B)
b)
ΔG‡a - ΔG‡b (the difference in activation energies)
c)
The temperature
d)
The concentration of reactants
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