5 . B
Carboxylic acids are the second most oxidized form of carbon (only carbon dioxide is more
oxidized). In carboxylic acids, the carbon atom has three bonds to oxygen. In aldehydes, the
carbon atom has two bonds to oxygen. In amines, the carbon atom has one bond to nitrogen. In
an alkane, the carbon only has bonds to other carbons and hydrogens.6 . A
All that we need to know about cinnamaldehyde is that it is an aldehyde, and therefore will be
reduced by a strong reducing agent like LiAlH 4 to a primary alcohol.7 . C
Because 2-butanol is a secondary alcohol, oxidation by a strong oxidizing agent like dichromate
will result in a ketone, butanone.8 . C
Pyridinium chlorochromate is a weak oxidizing agent, and will oxidize an alcohol to an aldehyde.
Stronger oxidizing agents are required to convert a primary alcohol to a carboxylic acid.9 . B
An SN1 reaction is a first-order nucleophilic substitution reaction. It is called first-order because
the rate-limiting step involves only one molecule. Choice (A) is true, but does not explain why SN 1
reactions have first-order kinetics; the rate-limiting step of an SN2 reaction is also the first (and
only) step of that reaction, but SN2 reactions have second-order kinetics, not first-order. Choice
(C) is a true statement as well, but again does not explain why the reaction is first-order. Finally,
choice (D) is incorrect because it is the rate-limiting step, not the reaction overall, that involves
only one molecule.10 . D
In a protic solvent, the protons in solution can attach to the nucleophile, decreasing its
nucleophilicity. The larger the nucleophile, and the stronger its conjugate acid, the stronger the
nucleophile will be. Of the options given, Iā will therefore be the strongest nucleophile because it
is least likely to associate with the protons in solution.
11 . D
Primary and secondary alcohols can undergo oxidation because the carbon can form additional
bonds with oxygen while losing bonds to hydrogen. Choice (A), a tertiary alcohol; choice (B), a