Chemistry Midterm III Practice Exam

Molecules with the same molecular formula but different structural arrangements.

Non-superimposable mirror images of each other.

Stereoisomers that are not mirror images.

A carbon atom bonded to four different groups.

Isomers that differ in the arrangement of atoms in space.

A molecule with chiral centers but an overall achiral structure (superimposable on its mirror image).

The number of possible spatial arrangements. This specific example would have a number of stereochemical possibilities.

A compound potentially having a chiral center depending on its specific structure. Further information is needed to conclude whether it has a chiral center or not

Molecules that are mirror images of each other but are not superimposable.

A specific chiral molecule with designated stereochemistry at two carbon atoms, part of a class of compounds.

A measure of the rotation of plane-polarized light by an optically active substance.

A unimolecular nucleophilic substitution reaction involving a carbocation intermediate.

A bimolecular nucleophilic substitution reaction occurring in a single step.

The systematic naming of a chemical compound according to a set of rules.

A proportionality constant that quantifies how quickly a chemical reaction proceeds.

A property of a molecule that lacks reflection symmetry.

Nucleophilicity (ability to donate electrons) often parallels basicity (ability to accept protons) for nucleophiles with the same atom. However, this generally isn't true when nucleophiles have different atoms.

Nucleophiles in protic solvents (like water or alcohol) often have more available electrons to share because they don't become heavily associated with the solvent.

Nucleophiles in aprotic solvents (without readily accepting protons, like acetone) can be strongly affected by charge interactions. This can lead to differences in nucleophilicity compared to basicity

The ability of a group to leave a molecule in nucleophilic substitution reactions, Br⁻ > Cl⁻ > OH⁻ > H⁻

SN1 reactions, which proceed through carbocation intermediates, are favored by polar protic solvents, such as water; polar solvents help stabilize the carbocation intermediate.

SN2 reactions, which proceed through a backside attack, are favored by polar aprotic solvents. These solvents don't interfere with the nucleophilic attack.

The solvent which supports the fastest reaction rate depends on the specific reaction type.

Consider factors like steric hindrance, nucleophile strength, and the leaving group ability to determine the rate of an SN2 reaction.