A racemic mixture is formed by mixing two:

1. Isomeric compounds             

2. Chiral compounds

3. Meso compounds                       

4. Enantiomers

Which of the following acid does not exhibit optical isomerism?

1. Maleic acid                           
2. $\mathrm{\alpha }$-amino acid

3. Lactic acid                             
4. Tartaric acid                             

The prefix used for -SH group as per the IUPAC system is-

1. Mercapto

2. Thiol

3. Sulfide

4. None of the above

Acetaldehyde reacts with

1. only electrophiles

2. only nucleophiles

3. only free radicals

4. both electrophiles and nucleophiles

Which of the following compounds has the lowest boiling point?

1. ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_3$ 

2 ${\mathrm{CH}}_3\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}}_2{\mathrm{CH}}_3$

3. ${\mathrm{CH}}_3\mathrm{CH}=\mathrm{CH}-\mathrm{CH}={\mathrm{CH}}_2$

4. ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_3$

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

1. Benzene                     

2. Ethene

3. Ethyne                         

4. Ethane

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 

Ethanol and dimethyl ether form a pair of functional isomers. The boiling point of ethanol is higher than that of dimethyl ether due to the presence of

1. H-bonding in ethanol 

2. H-bonding in dimethyl ether

3. $-{\mathrm{CH}}_3$ group in ethanol 

4. $-{\mathrm{CH}}_3$ group in dimethyl ether

Among the following the strongest acid is                                 

1. CH₃COOH

2. CH₂ClCH₂COOH

3. CH₂ClCOOH

4. CH₃CH₂COOH

Which one of the following pairs represents stereoisomerism?                                     

1. Chain isomerism and rotational isomerism

2. Structural isomerism and geometrical isomerism

3. Linkage isomerism and geometrical isomerism

4. Optical isomerism and geometrical isomerism