Test Prep Test Prep Certifications OAT Questions & Answers

• Question 1:

  Predict the product of the following reaction: A. Option A

  

  

  B. Option B

  C. Option C

  D. Option D

  E. Option E

  Correct Answer: E

  The NH3 is an activating, ortho/para director, and is capable of yielding the 2 products shown in A and C.

• Question 2:

  How many possible stereoisomers are there for this molecule?

  

  B. 3

  C. 4

  D. 5

  E. 6

  Correct Answer: C

  The maximum number of stereoisomers is determined by the equation: 2n Where n = number of chiral centers. There are 2 chiral centers in the molecule above, thus rendering a

  maximum number of 4 stereoisomers.

• Question 3:

  You are interested in extracting a specific carboxylic acid only in a mixture containing amines, ketones and phenols. Which of the following can be used to accomplish this?

  A. NaOH

  B. HCl

  C. NaHCO3

  D. H2O

  E. A and C

  Correct Answer: C

  This is an organic lab question that deals with extraction. In order to extract the carboxylic acid only, you can only use sodium bicarbonate. Although NaOH is capable of extracting the carboxylic acid, it will also extract the phenol, which is not what the question asks.

• Question 4:

  An IR chart showed a distinct peak at ~1710 cm-1. Which of the following does the peak represent best in an unknown compound?

  A. C = C

  B. C = O

  C. O – H (alcohol)

  D. Aromatic C – C

  E. N – H

  Correct Answer: B

  A carbonyl has a distinct peak at ~1710 whereas a C = C bond as a peak at ~1650. Alcohols (−OH) have a broad peak around 3300, as do N – H bonds (not as broad as −OH however).

• Question 5:

  Which of the following best describes the relationship between the 2 products below?

  

  A. Enantiomers

  B. Diastereoisomers

  C. Identical compounds

  D. Constitutional isomers

  E. 2 of the above

  Correct Answer: C

  Simply flipping anyone of the products will make it look identical to the other, thus they are simply the same compound.

• Question 6:

  Which of the following represents a possible product for the following reaction?

  

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  E. Option E

  Correct Answer: D

  This is a Wolff-Kishner reaction, that basically removes a carbonyl, leaving a methylene. Know the reaction itself and the name.

• Question 7:

  In numbering and naming a chain, which of the following functional groups receives the highest priority?

  A. Carboxylic acids

  B. Aldehydes

  C. Ketones

  D. Amines

  E. Alkynes

  Correct Answer: A

  Generally, carboxylic acids (and its derivatives like amides, esters etc.) have the highest priority.

• Question 8:

  For the following reaction, which is a possible reagent that can be used to attain this product?

  

  A. 1) H4N2 / H2O 2) KOH / N2

  B. Zn (Hg) / HCl, heat

  C. Br2, NaOH, H2O / heat

  D. H2 / Pt

  E. None of the above

  Correct Answer: C

  This is a Hofmann rearrangement reaction which converts a primary amide to a primary amine. Note the loss of the carbon.

• Question 9:

  What is the end product for the following set of reactions:

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  E. Option E

  Correct Answer: C

  The correct answer is C for all the following reactions. Answer choice A illustrates the product after the first reaction. Answer choice B illustrates the product after the second reaction, and finally C shows the product for the last reaction.

• Question 10:

  Which of the following can reduce an acid chloride to an alcohol?

  A. NaBH4

  B. DIBALH

  C. LiAlH4

  D. Heat

  E. A and C

  Correct Answer: E

  Both NaBH4 and LiAlH4 can reduce an acid chloride to a first-degree alcohol.

  DIBALH reduces an ester to an aldehyde.