A carbonyl functional group takes the form of . This leaves the carbonyl carbon to form two remaining bonds with various substituents. If one of these substituents is a hydrogen, the molecule is an aldehyde (the carbonyl group is at the end of the carbon chain). If neither substituent is a hydrogen, the molecule is a ketone (the carbonyl group is not at the end of the carbon chain).

An acid contains the carboxylic acid functional group, which takes the form of . Carbonyl groups do not contain the .

Amino acids contain the carboxylic acid functional group () and an amine functional group (). The description in the question does not fit this molecule.

There is no p orbital surrounding the Boron atom, so the ring does not have a fully conjugated pi system. In addition, there are 8 electrons, which does not follow Huckel's rule (an aromatic system contains 4n+2 electrons). The pi electrons include the lone pair (not shown, but implicit) on the nitrogen atom, which is why the answers with "6 electrons" are not correct.

Hydrogenation of a double bond involves the bond breaking and a hydrogen being added to each carbon of that double bond. You can tell the number of double bonds by taking the number of hydrogens added and dividing it by 2.

6 added hydrogen divided by 2 is 3 double bonds.

A hydrocarbon with zero degrees of unsaturation and carbons has hydrogens. For every two hydrogens less than , there is one degree of unsaturation. After hydrogenation, our final product has no double bonds. After calculation, we see that it has two degrees of unsaturation. This means that it has two rings.

The reaction shown is a Markovnikov addition of a hydracid (HX) across a double bond. According to Markovnikov's rule, the hydrogen gets added to the lesser-substituted carbon in the double bond, and the halide (in this case, ) gets added to the more-substituted carbon. Thus, the correct answer is .

E1 reactions occur in two steps. First, the leaving group is removed, yielding a carbocation. Second, a weak base removes a proton from the carbon adjacent to the carbocation carbon. Thus, to favor E1, a protic solvent is desired in order to stabilize the carbocation. Weak bases favor an E1 mechanism.

An elimination reaction occurs when there is a release of atoms in a given compound to produce two or more products. In the reaction given a hydrogen and chloride atom are eliminated from the original compound to form hydrochloric acid and ethylene.

The longest carbon chain is carbons long (thus ""), and the lack of double bonds makes it an alkane (thus ""). The highest priority functional group is the carboxylic acid group, and the suffix of the IUPAC name should reflect the highest priority functional group (thus ""). Because the carboxylic acid group is assumed to lie on carbon number there is no need to designate a locand for this functional group. The other substituents of this molecule are the methyl groups on carbons and when numbering the chain from left to right. Thus, the name is .

Aldehydes are carbonyls with one R-group and one hydrogen attached to the carbonyl carbon.

A carbonyl functional group takes the form of . This leaves the carbonyl carbon to form two remaining bonds with various substituents. If one of these substituents is a hydrogen, the molecule is an aldehyde (the carbonyl group is at the end of the carbon chain). If neither substituent is a hydrogen, the molecule is a ketone (the carbonyl group is not at the end of the carbon chain).

An acid contains the carboxylic acid functional group, which takes the form of . Carbonyl groups do not contain the .

Amino acids contain the carboxylic acid functional group () and an amine functional group (). The description in the question does not fit this molecule.

1. Benzene

2. Imine

3. Aldehyde