$\mathrm{\alpha }$-D-glucose and $\mathrm{\beta }$-D glucose have a specific rotation of +112$°$ and +19$°$ respectively. In aqueous solution the rotation becomes +52$°$. This process is called:

1. inversion                 

2. racemisation

3. mutarotation             

4. embolism

A racemic mixture is formed by mixing two:

1. Isomeric compounds             

2. Chiral compounds

3. Meso compounds                       

4. Enantiomers

A compound of molecular formula C₇H₁₆ shows optical isomerism, the compound will be

1. 2,3-dimethyl pentane 

2. 2,2-dimethyl butane 

3. 2-methyl hexane 

4. None of the above

Which of the following has an asymmetric carbon atom?

1. 

2. 

3. 

4. 

Stereoisomers (geometrical or optical) that are neither superimposable nor a mirror images to each other are called:

1. Enantiomers             

2. Monomers

3. Tautomers               

4. Diastereomers

Diastereomers can be separated by:

1. Recrystallization            

2. simple distillation

3. electrophoresis                     

4. all of these

Which of the following pairs of carbon skeletons is an example of isomerism?

1.
2.
3.
4.

1. 

2. 

3. 

4.  

The number of isomeric structures for C₂H₇N would be:

1. 4 

2. 3

3. 2 

4. 1

Number of isomers possible for C₄H₈ are-

1. 4     

2. 3       

3. 2     

4. 6

The dihedral angle between the hydrogen atoms of two methyl groups in staggered conformation of ethane is:

1. 120° 

2. 180°

3. 90° 

4. 60°