Which of the following pairs of compounds could be separated by recrystallization or distillation?
(c)

Verified step by step guidance

1. Analyze the chemical structures provided: The two compounds are diastereomers, as they have the same molecular formula and connectivity but differ in the spatial arrangement of their bromine substituents.
2. Understand the physical properties of diastereomers: Diastereomers typically have different physical properties, such as melting points and boiling points, which makes them separable by physical methods.
3. Consider recrystallization: Recrystallization is effective for separating compounds with different solubilities in a given solvent. Check if the diastereomers have significantly different solubilities in a suitable solvent.
4. Consider distillation: Distillation is effective for separating compounds with different boiling points. Check if the diastereomers have sufficiently different boiling points to allow separation by this method.
5. Choose the appropriate method: Based on the analysis of solubility and boiling point differences, determine whether recrystallization or distillation is the more suitable method for separating these diastereomers.

Key Concepts

Recrystallization

Recrystallization is a purification technique used to separate compounds based on their solubility differences. In this process, a solid compound is dissolved in a hot solvent and then allowed to cool, leading to the formation of pure crystals. The impurities remain dissolved in the solvent, allowing for the isolation of the desired compound. This method is particularly effective for separating compounds with different melting points.

Distillation

Distillation is a separation technique that exploits differences in boiling points of compounds. In this process, a mixture is heated to vaporize the more volatile component, which is then condensed back into a liquid and collected separately. This method is commonly used for purifying liquids and can effectively separate compounds that have significantly different boiling points, making it suitable for mixtures of liquids.

Stereoisomers

Stereoisomers are compounds that have the same molecular formula and connectivity of atoms but differ in the spatial arrangement of their atoms. This category includes enantiomers and diastereomers, which can exhibit different physical properties. Understanding stereoisomerism is crucial for separation techniques like recrystallization and distillation, as these methods can exploit differences in the physical properties of stereoisomers to achieve effective separation.