Quiz

QUIZ

1. What is not a characteristic feature of a ketone?

a. Carbonyl group b. Resonance between carbon and hydrogen c. Acidity d. Double bonding

Answer: c. These are all features of ketones, with the exception of acidity. Ketones are generally not acidic unless they have a particular functional group on them.

2. What is not a difference between the carbonyl double bond in a ketone and the carbon-carbon double bond in an alkene?

a. The ketone involves a pi bond, while the alkene double bond does not. b. The ketone double bond is polar, while the alkene double bond is not. c. There is greater energy in the double bond of the ketone compared to the

C-C double bond. d. The reaction with water proceeds more rapidly in a ketone than in an alkene.

Answer: a. Both of these bonds involve both a sigma bond and a pi bond, making for a relatively stable double bond.

3. What is the common name for the aldehyde called ethanal?

a. Butyraldehyde b. Formaldehyde c. Metaldehyde d. Acetaldehyde

Answer: d. Acetaldehyde is a two-carbon aldehyde that contains a methyl group and the carbonyl group. It can be made from acetic acid.

4. How many carbon atoms exist in the butyraldehyde molecule?

a. Three b. Four c. Five d. Six

Answer: b. Butyraldehyde is also referred to as butanal, which is a fourcarbon chain aldehyde.

5. Which of these descriptive terms is not the same as the others?

a. Acetone b. Dimethyl ketone c. Propanone d. Methyl phenyl ketone

Answer: d. Each of these is the same molecule, representing CH3COCH3, except for methyl phenyl ketone, which is another molecule that needs to be memorized.

6. What is not true of a combination ketone and aldehyde molecule?

a. The ketone takes precedence over the aldehyde b. The molecule has the term “oxo” in it. c. The number one carbon atom is the aldehyde carbonyl carbon. d. The substance is referred to as an aldehyde.

Answer: a. In the molecular name, the ketone does not take precedence over the aldehyde but the aldehyde instead takes precedence and the term has “oxo” in it to identify the second carbonyl group.

7. The molecule 5-hydroxy-3-pentenal has all but what type of features?

a. Ketone carbonyl group b. Alcohol side chain c. Alkene double bond d. Aldehyde carbonyl group

Answer: a. This is clearly an aldehyde by the “al” ending and has an “enal” ending because of the alkene double bond. The alcohol does not take precedence but is present at the 5th carbon atom.

8. In the carbonyl functional group, the oxygen is considered electronegative because it has how many unbonded electrons associated with it?

a. One b. Two c. Three d. Four

Answer: d. There are two pairs or “four” unbonded electrons associated with the oxygen molecule in the carbonyl functional group, which leads to the polarity of the carbon-oxygen bond.

9. A carboxylic acid is known to contain what functional group?

a. CHO b. CH2O c. COOH d. CH3CHO

Answer: c. The COOH side chain is characteristic of a carboxylic acid. This tends to be more reactive than the aldehyde and ketone carbonyl group.

10. There are a great many carboxylic acids to memorize. Which is the smallest carboxylic acid?

a. Formic acid b. Acetic acid c. Propionic acid d. Capric acid

Answer: a. Formic acid is very small, consisting of HCOOH, making it the smallest possible carboxylic acid.