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 of the following is more basic than aniline?                    

1. Diphenylamine

2. Triphenylamine

3. p-nitroaniline

4. Benzylamine

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

1. Benzene                     

2. Ethene

3. Ethyne                         

4. Ethane

Which one of the following compounds is most acidic?                                   

1. 

2. 

3. 

4. 

Which of the following represents the correct order of acidity in the given compounds?

1. F${\mathrm{CH}}_2$COOH > ${\mathrm{CH}}_3$COOH > Br${\mathrm{CH}}_2$COOH > Cl${\mathrm{CH}}_2$COOH

2. Br${\mathrm{CH}}_2$COOH > Cl${\mathrm{CH}}_2$COOH > F${\mathrm{CH}}_2$COOH > ${\mathrm{CH}}_3$COOH

3. F${\mathrm{CH}}_2$COOH > Cl${\mathrm{CH}}_2$COOH > Br${\mathrm{CH}}_2$COOH > ${\mathrm{CH}}_3$COOH

4. ${\mathrm{CH}}_3$COOH > Br${\mathrm{CH}}_2$COOH > Cl${\mathrm{CH}}_2$COOH > F${\mathrm{CH}}_2$COOH 

Among the following, the strongest acid is: