Stereochemistry and aromaticity UE Past Papers Questions.

In chair conformers of substituted eyelohexane large substituent groups prefer

1. The axial position to avoid 1,3 diaxial interactions
2. The equatorial position to avoid 1,2 diaxial interactions
3. The axial position to avoid 1.3 diaxial interactions
4. The equatorial position to avoid 1,3 diaxial interaction

Answer / Solution

UNSOLVED

How many chiral centers are in the molecule with the formula

1. 2
2. 3
3. 4
4. 8

Answer / Solution

UNSOLVED

Cis and trans isomers of 1,2-dichloroethane have;

1. The same boiling point
2. Different melting point
3. The same level of polarity
4. Different density

Answer / Solution

UNSOLVED

Suppose you are provided with R-thalidomine and S-thalidomine, what is streochemical relationship of the two compounds.

1. Diastereomers
2. Optical isomers
3. Enantiomers
4. Enatiomeric pure drug

Answer / Solution

UNSOLVED

Cyclopropane when burnt in air produces more energy than propane due to;

1. Higher molecular weight of cyclopropane
2. Angle strain
3. Higher intermolecular forces in cyclopropane
4. Unreactive state of cyclopropane.

Answer / Solution

UNSOLVED