Test: Stereoisomerism - JEE MCQ

 2-bromomethyl-2-methyl-1-butanol: The bromine substitution occurs at the carbon bonded to oxygen but not at a chiral carbon. Thus option b satisfies the condition.

Option b: Decrease concentration of sample four times and measure the optical rotation. Explanation:

• Optical rotation is directly proportional to concentration (specific rotation = observed rotation/concentration).
• If you decrease the concentration of the chiral compound in the sample, the observed optical rotation will decrease proportionally.
• If the initial observed rotation is indeed +60° and not -300°, decreasing the concentration will still result in a positive rotation, but it will be lower.

The other options are less likely to provide useful information in this context.

The correct answer is option C
1,4-Dimethylcyclohexane consists of two diastereomeric stereoisomers, although, according to the n2 rule, four stereoisomers should be expected due to the fact that 1,4-dimethylcyclohexane contains two asymmetric carbons.

The correct answer is option b. It has a center of symmetry: This statement is incorrect. A center of symmetry requires that for every atom at a certain position, there is an identical atom at an equal distance but opposite in direction. The given compound lacks a center of symmetry

The correct answer is option c

The above product is meso form of an isomer which is a type of stereoisomer that possesses an internal plane of symmetry. This symmetry leads to identical or equivalent substituent groups on either side of the plane, resulting in an overall non-chiral (achiral) molecule. Despite having stereocenters, the meso form does not exhibit optical activity because any rotation around the internal plane of symmetry can interconvert its mirror-image configurations, making them superimposable.

The correct answer is 8

Chiral Carbon
Carbon no.1 is chiral carbon so H Show 2 optical isomers
Carbon no.3 is also chiral carbon 
Hence, shows two optical isomers
Carbon 1 & carbon 3 shows G.I. due to 1 stereocenter
Propenyl shows 2 G.I.
Total 8 isomers are shown here.

The correct answer is 4 Since there are three different types of H and it gives three monochlorinated product. One of them is optically active and exists as an enatiomeric pair. So there is a total of four different products.

All the highlighted position are chiral centres.

The number of pairs of diastereomers for a given compound can be determined by considering the presence of chiral centers. Diastereomers are stereoisomers that are not mirror images of each other, and they have different configurations at one or more chiral centers.

There are 9 isomers of C₃H₂Cl₂.
They are:-

The correct answer is 4

2-chloro-4-methyl hex-2-ene has a double bond, so has two geometrical isomers.
It has one asymmetric carbon atom.
So, it has 2 optical isomers
So, total isomers =2+2=4

Correct answer is 6 
Because it can exist in the keto form and a indol form and it was isomerization taking place during 
chromatography which causes the G c peak to  diffuse

The correct answer is Option A.

Racemic mixture is an equimolecular mixture of enantiomeric pairs. The rotation caused by the molecules of one enantiomer is cancelled by the rotation caused by the molecules of another enantiomer.
 

The correct answer is: a.

Both Statement I and Statement II are correct, and Statement II is the correct explanation of Statement I. Cis-1,4-dichlorocyclobutane is indeed optically inactive because it possesses a plane of symmetry. The plane of symmetry allows the molecule to be superimposable on its mirror image, making it achiral and, therefore, optically inactive. So, both statements are correct, and Statement II provides the correct explanation for why the compound is optically inactive.

The correct answer is:c

Statement I is correct but Statement II is incorrect

Explanation: Statement I suggests that decreasing the length of the sample tube decreases the magnitude of optical rotation. This is a valid statement because the length of the sample tube can influence the optical rotation of polarized light passing through an optically active substance. 

However, Statement II states that decreasing the length of the sample tube decreases the contribution of the sample tube material to the total optical rotation. This is not necessarily true. The contribution of the sample tube material to optical rotation depends on factors such as the specific optical properties of the material and the length of the tube. Simply decreasing the length of the tube does not necessarily decrease the contribution of the material, as it depends on the nature of the material itself.

Solution: the correct option is a

Compound i. have four stereoisomers, have two optically active isomers and have more than two pairs of diastereomers

Compound ii. have only three stereoisomers and have two optically active isomers

Compound iii. have four stereoisomers and have more than two pairs of diastereomers

Compound iv. have four stereoisomers and  have more than two pairs of diastereomers

Solution: the correct option is b

Enantiomers are optically active and can be separated into components

Diastereomers one pair of diastereomer is optically active (enantiomer one) and other is optically inactive (meso one), can be separated into two components and may have a plane of symmetry

Meso are optically inactive and may contain a plane of symmetry

Racemic Mixture are optically active and can be separated into two components