All Organic Chemistry Resources
Example Questions
Example Question #11 :Organic Functional Groups And Molecules
Assuming that this molecule is planar, determine whether this molecule is aromatic, and name the number ofelectrons (molecular orbitals).
Aromatic, 8electrons
Non aromatic, 6electrons
Aromatic, 6electrons
Not aromatic, 8electrons
Not aromatic, 8electrons
There is no p orbital surrounding the Boron atom, so the ring does not have a fully conjugated pi system. In addition, there are 8electrons, 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.
Example Question #12 :Organic Functional Groups And Molecules
Assuming that this molecule is planar, determine whether this molecule is aromatic, and name the number ofelectrons (notmolecular orbitals).
Not aromatic, 6electrons.
Aromatic, 6electrons.
Not aromatic, 8electrons.
Aromatic, 8electrons.
Aromatic, 6electrons.
The lone pairs on the two nitrogen atoms reside in sp2 orbitals, meaning they do not participate in resonance. Within the ring, there are threebonds, meaning there are sixelectrons. Thus, the molecule is aromatic because it is planar and follows Huckel's rule.
Example Question #13 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Ester
Ketone
Carboxylic acid
Acid anhydride
Aldehyde
Aldehyde
Aldehydes are carbonyls with one R-group and one hydrogen attached to the carbonyl carbon.
Example Question #14 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Ketone
Carboxylic acid
Acetal
Ester
Aldehyde
Ketone
Ketones are carbonyls with two R-groups attached the the carbonyl carbon.
Example Question #15 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Amide
Carboxylic acid
Ester
Acid halide
Acid anhydride
Acid halide
This is an acid halide, were X is any halogen (group VII). They are the most reactive of all the carboxylic acid derivatives.
Example Question #16 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Aldehyde
Acid anhydride
Ester
Carboxylic acid
Ketone
Carboxylic acid
Carboxylic acids are composed of one R goup and a hydroxy group bound to the carbonyl carbon. The hydroxyl group gives the molecule acidic properties.
Example Question #17 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Aldehyde
Acid anhydride
Acetal
Hemiketal
Ester
Hemiketal
This is a hemiketal. Hemiketals are formed from the reaction of a ketone with an alcohol. The alcohol attacks the carbonyl carbon, reducing the double bond and adding a hydroxyl group.
Example Question #18 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Ketal
Hemiketal
Hemiacetal
Acetal
Acid anhydride
Ketal
Ketals have two -OR groups bound to a central carbon. The R groups attached to the oxygens are not necessarily the same. Ketals result from the reaction of a ketone with two equivalents of alcohol.
Example Question #1 :Identifying Carbonyl Compounds
Identify the given organic functional group.
Carboxylic acid
Acid anhydride
Ester
Hemiacetal
Acetal
Acid anhydride
Acid anhydrides are relatively reactive, since they have a fairly good leaving group (the conjugate base of a carboxylic acid) [COO-]. They are formed by reacting two carboxylic acids via dehydration synthesis.
Example Question #20 :Organic Functional Groups And Molecules
Identify the given organic functional group.
Amide
Amine
Ester
Imine
醚
Amide
This is an amide. It is very unreactive since its leaving group is the conjugate base of an amine [HNR-].