DH QUESTION 1 [11] Give reasons that might help to explain the following observations: a) A student was unsuccessful to prepare a Grignard reagent from 4-bromocyclohexanol. b) Benzenesulfonic acid does not undergo Friedel-Crafts alkylation. c) (2S, 3R)-2,3-Dibromobutane has a specific rotation, [a]o, of 0°. d) A student tries to prepare an ether via the Williamson ether synthesis from ethanol and t-butyl bromide, but obtains an alkene instead. e) Doubling the concentration of a nucleophile has no effect on the rate of a substitution reaction.