Which of the following may exist as enantiomers?

1.
2.	\(\mathrm{CH}_2=\mathrm{CHCH}_2 \mathrm{CH}_2 \mathrm{CH}_3 \)
3.
4.

The total number of isomers could be obtained from the alkane, C₆H₁₄ is-

1. Four                   

2. Five

3. Six                    

4. Seven

CH₃-CHCl-CH₂-CH₃ has a chiral center. Which one of the following represents its R-configuration? 

1.

2. 

3. 

4. 

The number of primary carbon atoms in the following compound are:

4-methylpent-2-ene is  achiral because it has:

1. a centre of symmetry 

2. a plane of symmetry 

3. symmetry at C 4 carbon

4. both centre and a plane of symmetry 

The (R)- and (S)-enantiomers of an optically active compound differ in

1. their solubility in a chiral solvent

2. their reactivity with a chiral reagent

3. their optical rotation of plane polarised light

4. their melting points

The cylindrical shape of an alkyne is due to the presence of- 

1. Three sigma C-C bonds

2. Three π C-C bonds

3. Two sigma C-C and one π C-C bonds

4. One sigma C-C and two π C-C bonds

What is decreasing order of basicity of 1°, 2° and 3° ethyl amines and ammonia in aqueous medium?          

1. NH₃>C₂H₅NH₂>(C₂H₅)₂NH>(C₂H₅)₃N

2. (C₂H₅)₃N>(C₂H₅)₂NH>C₂H₅NH₂> NH₃

3. (C₂H₅)₃NH>C₂H₅NH₂>(C₂H₅)₃N>NH₃

4. (C₂H₅)₂NH>(C₂H₅)₃N>C₂H₅NH₂>NH₃

The shortest C-C bond distance is found in               

1. Diamond             

2. Ethane

3. Benzene             

4. Acetylene

Which one of the following has the shortest carbon-carbon bond length?                      

1. Benzene                     

2. Ethene

3. Ethyne                         

4. Ethane