Conformational Isomerism

Q.

The number of isomers of the compound C₂FClBrI is:

a.3

b.4

c.5

d.6

Q. Which of the following dihedral angle is not possible in skew conformation?

1. ${60}^{\circ }$
2. ${150}^{\circ }$
3. ${30}^{\circ }$
4. ${90}^{\circ }$

Q. In glyceraldehydes, sort the sequence of priority according to CIP rules.

1. $-OH$
2. $-CHO$
3. $-H$
4. $-C{H}_{2}OH$

Q. In the following skew conformation of ethane, $H^{\prime }-C-C-H^{\prime \prime }$ dihedral angle is

1. ${58}^o$
2. ${149}^o$
3. ${151}^o$
4. ${120}^o$

Q. Which is the correction expression for the magnitude of the equilibrium constant K for the following equilibrium?

1. K = 1
2. K < 1
3. K > 1
4. No estimate of K can be made

Q. 2, 2, 3, 3-Tetramethylbutane & Iso-octane are chain isomers.

1. True
2. False

Q. Which of the following is true regarding stability of eclipsed and staggered conformation?

1. Eclipsed conformation is more stable than staggered conformation
2. Eclipsed conformation is less stable than staggered conformation
3. Stability of eclipsed and staggered conformations are equal
4. None of the above

Q.

Energy barrier between staggered and eclipsed conformation of ethane is?

1. 0.6K Cal/ mole

2. 2.9 K Cal/ mole

3. 12 K Cal/ mole

4. 16 K Cal/ mole

Q. Which of the following isomer is not considered, while counting total number of isomers of any molecule?

1. Chain isomer
2. Position isomer
3. Conformational isomer
4. Geometrical isomer

Q. Which of the following dihedral angle is not possible in skew conformation?

1. ${60}^{\circ }$
2. ${150}^{\circ }$
3. ${30}^{\circ }$
4. ${90}^{\circ }$

Q.

Which of the following is the correct order of stability of the following four distinct conformations of n-butane?

1. Staggered > Gauche >Partially eclipsed > Fully eclipsed

2. Gauche Staggered > Partially Eclipsed > Fully eclipsed

3. Staggered > Partially eclipsed > Gauche >Fully eclipsed

4. Fully eclipsed > Staggered >Partially eclipsed > Gauche

Q. Which of the following bond, rotation is not permitted by conformational isomerism at room temperature?

1. $C\equiv C$ bond
2. $C=C$bond
3. $C-C$ bond
4. (a) and (b) above.

Q. Which is the most stable chair conformer of this compound?

1. 
2. 
3. 
4. 

Q. When two different 3D arrangements in space of the atoms in a molecule are interconvertible by free rotation about the single bonds, they are called:

1. Ring chain isomers
2. Conformational isomers
3. Functional isomers
4. All of the above

Q.

The number of conformations of ethane are:

1. 1
2. 2
3. 3
4. infinite

Q. Which of the following statement(s) is/are correct?

1. Cyclopropane has a non-planar structure.
2. Cyclobutane has a non planar structure.
3. Cyclopentane has a non planar structure.
4. Cyclopentane has a planar structure.

Q.

The number of isomers of the compound $C_{2}FClBrI$ is:

1. 3

2. 4

3. 5

4. 6

Q. Which of the following compound is most stable?

1. 
2. 
3. 
4.