Assuming no other changes, what is the effect of doubling both the alkyl halide and the nucleophile concentrations in the above reaction?()
A. no change
B. doubles the rate
C. triples the rate
D. quadruples the rate
E. rate is halved
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Which of the following statements is generally true for SN1 reactions?()
A. Complete inversion of configuration occurs.
B. These reactions are favored by nonpolar solvents.
C. These reactions are favored by polar solvents.
D. Reaction rates depend only on the concentration of the nucleophile.
E. The mechanism is a one-step back attack.
Which of the following best explains why SN1 reactions involving a neutral reactant are faster in polar solvents?()
A. The substrate is more soluble in polar solvents.
B. The substrate is less soluble in polar solvents.
C. The nucleophile is solvated by polar solvents.
D. Solvation by polar solvents stabilizes the carbocation.
E. Solvation by polar solvents stabilizes the transition state.
Protic and aprotic solvents are very similar as solvents except for their ________.()
A. polarity
B. dielectric constant
C. ability to stabilize anions by hydrogen bonding
D. ability to stabilize cations by hydrogen bonding
E. ability to stabilize cations with unshared pairs of electrons
Which of the following statements is true concerning the E2 reactions of alkyl fluorides?()
Alkyl fluorides react more readily in E2 reactions than do alkyl iodides.
B. The transition state of this E2 reaction resembles a carbanion rather than an alkene.
C. The C-F bond is the weakest carbon-halogen bond so SN2 will always predominate over E2 in the reactions of alkyl fluorides.
D. Alkyl fluorides react to form the most stable carbocation intermediate.
E. Alkyl fluorides cannot adopt the proper stereochemical alignment for an E2 reaction to occur.
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