Isomerism

CH3-CHCl-CH2-CH3 has a chiral centre. Which one of the following represents its R-configuration?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

If there is no rotation of plane polarised light by a compound in a specific solvent, though thought to be chiral, it may mean that

1. the compound is certainly meso
2. there is no compound in the solvent
3. the compound may be a racemic mixture
4. the compound is certainly achiral.

Which of the following is not chiral?

1. 2-Hydroxypropanoic acid
2. 2-Butanol
3. 2,3-Dibromopentane
4. 3-Bromopentane

The chirality of the compound [figure]

1. R
2. S
3. E
4. Z

Which one of the following pairs represents stereoisomerism?

1. Structural isomerism and geometrical isomerism
2. Optical isomerism and geometrical isomerism
3. Chain isomerism and rotational isomerism
4. Linkage isomerism and geometrical isomerism.

The molecular formula of diphenylmethane, [figure] is C13H12. How many structural isomers are possible when one of the hydrogens is replaced by a chlorine atom?

1. 6
2. 4
3. 8
4. 7

Which of the following pairs of compounds are enantiomers?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

In this reaction : CH3CHO + HCN CH3CH(OH)CN HOH CH3CH(OH)COOH an asymmetric centre is generated. The acid obtained would be

1. D-isomer
2. L-isomer
3. 50% D + 50% L-isomer
4. 20% D + 80% L-isomer

Geometrical isomers differ in

1. position of functional group
2. position of atoms
3. spatial arrangement of atoms
4. length of carbon chain

A compound of molecular formula C7H16 shows optical isomerism, compound will be

1. 2,3-dimethylpentane
2. 2,2-dimethylbutane
3. 2-methylhexane
4. none of these