In this reaction, CH₃CHO + HCN$\to$CH₃CH(OH)CN$\stackrel{\mathrm{H}.\mathrm{OH}}{\to }$CH₃CH(OH)COOH an asymmetric centre is generated. The acid obtained would be                                                                      

1. 50% D + 50% L-isomer

2. 20%D + 80% L-isomer

3. D-isomer

4. L-isomer

The -OH group of an alcohol or the -COOH group of a carboxylic acid can be replaced by -Cl using     

1. phosphorus pentachloride

2. hypochlorous acid

3. chlorine

4. hydrochloric acid

An ester is boiled with KOH. The product is cooled and acidified with conc. HCl. A white crystalline acid separates. The ester is

1. methyl acetate 

2. ethyl acetate

3. ethyl formate 

4. ethyl benzoate

The compound formed when malonic acid heated with urea, is                  

1. cinnamic acid

2. butyric acid

3. barbituric acid

4. crotonic acid

The dihedral angle between two C-H bonds in the staggered conformation of ethane  is            

1. 60$°$ 

2. 180$°$

3. 0$°$ 

4. 120$°$

Number of monochlorinated products (excluding stereo-isomers) obtained from the given reaction are :

 Which of the following compounds will exhibit cis-trans (geometrical) isomerism?

1. but-2-ene                             

2. Butanol

3. but-2-yne                             

4. buten-2-ol   

An alkane can form Structural isomers if the number of carbon atoms is-

1. $\ge$1                                 

2. $\ge$2

3. $\ge$3                                   

4. $\ge$4

Isomerism exhibited by acetic acid and methyl formate is:
1. Functional
2. Chain
3. Geometrical
4. Central 

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