Indicate whether each of the following pairs are identical, or enantiomers and diastereomers ?

	I	II	III
1.	enantiomers	diastereomers	enantiomers
2.	identical	enantiomers	enantiomers
3.	enantiomers	diastereomers	identical
4.	enantiomers	identical	identical

 

Which conformational form of 2-Fluoro ethanol is most stable ?

1. Anti

2. Partially eclipsed

3. Full eclipsed

4. Gauche

Total number of optical isomers obtained after monohalogenation of 3-Methylpentane are-

1. 2

2. 4

3. 6

4. 8

 has the configuration

1. R,R

2. S,S

3. R,S

4. May be 1 or 2

${\mathrm{C}}_4{\mathrm{H}}_6$ may have 

1. One triple bond

2. Two double bonds

3. Two cycles

4. All of the above

The number of chain isomers  for ${\mathrm{C}}_5{\mathrm{H}}_{12}$ and ${\mathrm{C}}_6{\mathrm{H}}_{14}$ are, respectively :

1. 3,3
2. 3,5
3. 4,4
4. 3,4

Total isomers for ${\mathrm{C}}_4{\mathrm{H}}_{10}\mathrm{O}$ are-

1. 4

2. 5

3. 7

4. 8

Which of the following is the most stable carbocation?

1.              2. 

3.  ${\left({\mathrm{CH}}_3\right)}_3 \stackrel{+}{\mathrm{C}}$         4.  ${\mathrm{CH}}_2=\mathrm{CH}-\stackrel{\oplus }{\mathrm{C}}{\mathrm{H}}_2$

Calculate the stereoisomers of the given molecule :

CH₃CH=CHCH₂C HBrCH₃

1. 4

2. 6

3. 8

4. 2 

Lassaigne's extract is boiled with conc. HNO₃ while testing for halogens. By doing so, it:

1. Helps in the precipitation of AgCl

2. Increases the solubility product of AgCl

3. Increases the concentration of NO₃^- ions

4. Decomposes Na₂S and NaCN, if formed.