Which of the following statements concerning SN2 reactions of alkyl halides is not correct?()
A. The rate of reaction depends on the concentration of the nucleophile.
B. The rate of reaction depends on the concentration of the alkyl halide.
C. The rate of reaction of a particular alkyl bromide depends on the steric accessibility of the carbon of the C-Br bond.
D. All alkyl iodides react more rapidly than all alkyl chlorides.
E. The rate of reaction depends on the relative nucleophilicity of the nucleophile.
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Which of the following correctly describes the relative nucleophilicities of methoxide and tert-butoxide?()
A. These alkoxides have essentially the same nucleophilicities since the negative charge in both is localized on an oxygen atom.
B. Methoxide is more nucleophilic because the nucleophilicity of tert-butoxide is diminished by steric effects.
C. tert-Butoxide is more nucleophilic because it contains three methyl groups which increase the charge on its oxygen by donating electron density.
D. tert-Butoxide is more nucleophilic because it is more basic.
E. none of the above
Which of the following is the rate law for SN1 mechanisms?()
A. Rate = k[Alkyl Halide] [Nucleophile]
B. Rate = k[Nucleophile]
C. Rate = k[Alkyl Halide]
D. Rate = k[Alkyl Halide] [Nucleophile] + k2[Alkyl Halide]
E. Rate = k1[Alkyl Halide] + k2[Nucleophile]
In the SN1 hydrolysis mechanism of (CH3)3CBr, there are ________ elementary steps, ________ distinct transition states, and ________ distinct intermediates.()
A. 2; 2; 2
B. 2; 2; 3
C. 2; 3; 2
D. 3; 2; 3
E. 3; 3; 2
Which of the following is the best leaving group?()
A. HO-
B. F-
Cl-
D. Br-
E. I-
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