Question

Choose the correct statement(s): (A) ' 8 ' brominated product will be obtained (B) ' 8 ' fractions will obtain on fractional distillation (C) ' 6 ' resolvable product will be obtained (D) ' 4 ' enantiomeric pair will be obtained

Short answer

In conclusion, without more context and information about the starting compounds and reaction conditions, it is not possible to determine the validity of any of these statements (A, B, C, or D).

Step-by-step solution

Understand the terms

Brominated product: A brominated product is a compound that has been treated with bromine, forming a product containing one or more bromine atoms. Fractional distillation: This is a separation process used to separate mixtures of substances with different boiling points. The process involves heating the mixture to vaporize the components, then condensing and collecting the individual components based on their boiling points. Resolvable product: A resolvable product is a compound that can be separated into its individual stereoisomers. Stereoisomers are molecules with the same chemical formula and connectivity but different arrangements of atoms in space. Enantiomeric pair: An enantiomeric pair consists of two molecules that are mirror images of each other and are not superimposable. They are a type of stereoisomer called enantiomers.

Evaluate statement (A)

(A) ' 8 ' brominated product will be obtained: To determine the number of brominated products, we would need information about the starting compound(s), the reaction conditions, and the mechanism of bromination. Without this information, we cannot accurately assess the statement's validity.

Evaluate statement (B)

(B) ' 8 ' fractions will obtain on fractional distillation: As with statement (A), this statement cannot be confirmed without more information about the compounds involved and their boiling points. Fractional distillation depends on the separation of components based on their boiling points, so we need detailed information about the components to make a judgment on this statement.

Evaluate statement (C)

(C) ' 6 ' resolvable product will be obtained: Again, this statement is difficult to evaluate without proper context. To assess the validity of this statement, we need to know the starting compound(s), the reaction mechanism, and the stereochemistry of the products. Then, we can determine which products are resolvable or not.

Evaluate statement (D)

(D) ' 4 ' enantiomeric pair will be obtained: Similar to the previous statements, this statement cannot be confirmed without more information about the starting compounds and the stereochemistry of the products formed. Once we have this information, we can analyze if there are indeed 4 enantiomeric pairs. In conclusion, without more context and information about the starting compounds and reaction conditions, it is not possible to determine the validity of any of these statements.

Key concepts

Bromination in Organic Chemistry

Bromination is a fundamental reaction in organic chemistry where a bromine atom is introduced into an organic molecule. This chemical process is used in the synthesis of various brominated compounds, which are integral in pharmaceuticals, agrochemicals, and other industries.

In the context of JEE exam preparation, understanding the mechanism by which bromination occurs is crucial. Typically, these reactions follow a free radical mechanism when alkanes are involved, or an electrophilic addition mechanism with alkenes. In the presence of sufficiently reactive compounds, multiple bromine atoms may be added, leading to a variety of products.

It's worth noting that predicting the number of possible brominated products requires a detailed understanding of the starting material’s structure, as well as the reaction conditions, such as solvents, temperature, and presence of light. For instance, symmetrical molecules would yield fewer distinct brominated products upon reaction with bromine, compared to asymmetrical ones which might produce a diverse set.

Fractional Distillation

Fractional distillation is a pivotal technique in chemistry for separating a mixture into its individual components or fractions, based on differences in their boiling points. It’s commonly used when components have boiling points that are close to each other.

The separation is achieved in a fractionating column, where the vaporized mixture rises, and as it cools down, the component with the higher boiling point condenses first and can be collected. The efficiency of the distillation depends on the length of the fractionating column—the longer the column, the better the separation.

For students tackling problems related to fractional distillation in JEE Main and Advanced exams, it is essential to comprehend how the process is affected by the boiling points and the volatility of the compounds. Understanding Raoult’s law and Dalton’s law can also be important for deciphering more complex distillation problems.

Stereochemistry

Stereochemistry is the study of the spatial arrangement of atoms within molecules and how this affects their chemical behavior and properties. An understanding of stereochemistry is crucial for predicting the reactivity and physical properties of organic compounds.

Students need to be familiar with concepts such as chirality, stereoisomers, and conformational isomerism. Chirality, in particular, describes a molecule’s property of not being superimposable on its mirror image, much like one's left and right hands. This concept lays the groundwork for understanding more complex ideas in stereochemistry, including enantiomers, diastereomers, and racemic mixtures.

Identifying Chiral Centers

One of the key aspects of stereochemistry that JEE candidates must master is the identification of chiral centers in molecules—carbon atoms with four different substituents. Knowing how to identify these centers can help in predicting the number of stereoisomers a compound can have.

Enantiomers

Enantiomers are a pair of stereoisomers that are non-superimposable mirror images of each other, much like one's left and right hands. In a chemical context, they share the same molecular formula and the same connectivity between atoms, but differ in the three-dimensional arrangement of atoms in space.

In organic chemistry, this 3D arrangement can significantly impact a molecule's interaction with other chiral molecules, including biological macromolecules like proteins and enzymes. Therefore, understanding the concept of enantiomers is not only crucial for JEE Main and Advanced exams but also for its applications in drug design and pharmaceuticals.

Importance of Enantiomeric Purity

The concept of enantiomeric excess and optical activity are related phenomena that are important when discussing enantiomers. Enantiomeric excess is a measure of the purity of a sample that contains a pair of enantiomers, and optical activity pertains to the ability of chiral molecules to rotate plane-polarized light, which is a method to distinguish between enantiomers.