Soap is a salt of a carboxylate anion with a long hydrocarbon tail. Choices (A) and (B) are not
salts of anionic compounds. Choice (D) is sodium acetate, which is a salt but does not contain the
long hydrocarbon tail needed to be considered a soap.5 . B
Jones reagent (chromium trioxide in aqueous sulfuric acid) is an oxidizing agent. As such, it
oxidizes primary alcohols directly to carboxylic acids. This reagent is too strong an oxidant to give
an aldehyde, so choice (A) is incorrect; remember that pyridinium chlorochromate (PCC) is a
common oxidizing agent used to convert alcohols to aldehydes without progressing to a
carboxylic acid. Choice (D), a dicarboxylic acid, cannot form because there is no functional group
on the other end of the molecule for the reagent to attack, and it cannot attack an inert alkane.
Choice (C) represents reduction, not oxidation.
6 . C
Carboxylic acids cannot be converted into alkenes in one step. Esters, choice (A), are formed in
nucleophilic acyl substitution reactions with alcohols. Amides, choice (B), are formed by
nucleophilic acyl substitution reactions with ammonia. Alcohols, choice (D), may be formed
using a variety of reducing agents. To form alkenes, carboxylic acids may be reduced to alcohols,
which can then be transformed into alkenes by elimination in a second step.
7 . D
Lithium aluminum hydride (LiAlH 4 or LAH) is a strong reducing agent. LAH can completely reduce
carboxylic acids to primary alcohols. Aldehydes are intermediate products of this reaction;
therefore, choice (A) is incorrect. The other compounds are not created through the reduction of
a carboxylic acid.
8 . D
Micelles are self-assembled aggregates of soap in which the interior is composed of long
hydrocarbon (fatty) tails, which can dissolve nonpolar molecules. The outer surface is covered
with carboxylate groups, which makes the overall structure water-soluble. Soaps, in general, are
salts of long-chain hydrocarbons with carboxylate head groups.
9 . D
The reaction described is esterification, in which the nucleophilic oxygen atom of 1-pentanol
attacks the electrophilic carbonyl carbon of butanoic acid, ultimately displacing water to form
pentyl butanoate. The acid catalyst is regenerated from 1-pentanol's released proton. Choice (A)