This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Chemistry 14D Fall 2009 Exam 1 Solutions Page 1 Statistics : High score, average, and low score will be posted on the course web site after exam grading is complete. The exam is ready to be picked up when these numbers are posted. Some questions have more than one answer, even though only one answer may be listed here. To see the projected course grade cutoffs, consult the grading scale on the Chemistry 14D course web page. 1. 2. (a) Slower. C 6 F 5 S- is a poorer nucleophile than C 6 H 5 S- due to the fluorine electron withdrawing inductive effects . (b) Faster. CH 3 S- is a better nucleophile than C 6 H 5 S- due to a lack of resonance delocalization of charge . (c) Slower. Compared to a methyl group, the tert-butyl group provides greater steric hindrance to approach of the nucleophile . (d) Faster. The energy of activation for an S N 2 reaction involving one or more reactants with formal charge is lowest when the solvent is less polar . (e) Faster. The energy of activation for an S N 2 reaction involving one or more reactants with formal charge is lowest when the solvent is less polar . (f) Slower. Chloride ion is a poorer leaving group than iodide ion . (g) No significant change. Changing the alkene to an alkane does not have a significant steric effect, nor does it change the nature of the nucleophile, leaving group, or solvent ....
View Full Document
- Winter '08
- Chemistry, Nucleophilic substitution, Steric effects, Carbocation, better leaving group