A carbonyl compound reacts with hydrogen cyanide to form cyanohydrin which on hydrolysis forms a racemic mixture of $\mathrm{\alpha }$-hydroxy acid. The carbonyl compound is

1. acetaldehyde 

2. acetone

3. diethyl ketone 

4. formaldehyde                              

 A and B in the following reactions are $\underset{\mathrm{KCN}}{\overset{\mathrm{HCN}/}{\to }}$A$\stackrel{\mathrm{B}}{\to }$

1. A=${\mathrm{RR}}^{\text{'}}{\mathrm{CH}}_2\mathrm{CN}$, B=NaOH

2. A=, B=${\mathrm{CH}}_3$

3. A=, B=${\mathrm{CH}}_3$

4. A=, B=${\mathrm{LiAlH}}_4$

Consider the following reaction,

Phenol$\stackrel{\mathrm{Zn}-\mathrm{dust}}{\to }$X$\underset{\mathrm{Anhy}.{\mathrm{AlCl}}_3}{\overset{{\mathrm{CH}}_3\mathrm{Cl}}{\to }}$Y$\stackrel{\mathrm{Alk}.{\mathrm{KMnO}}_4}{\to }$Z 

The product Z is                            

1. toluene

2. benzaldehyde

3. benzoic acid

4. benzene

Trichloroacetaldehyde, CCl₃CHO reacts with chlorobenzene in the presence of sulphuric acid and produces                                                                         

1. 

2. 

3. 

4. 

What is formed when a primary alcohol undergoes catalytic dehydrogenation?

1. Aldehyde 

2. Ketone 

3. Alkene

4. Acid