Which separation technique is optimal for purification of small sample sizes and employs a stationary phase, a solvent mobile phase (under pressure), and a detector to separate compound mixtures based on polarity?

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11ecba2d_1287_b130_a3bf_61da5620e6b4_MD0008_00 Organic reactions generally do not produce a single product; therefore, separation and purification methods are imperative to obtain the compound of interest. There exist several techniques to separate compounds based on their physical properties, including boiling point, solubility, and polarity. High-performance liquid chromatography (HPLC) is a purification technique comprised of a mobile phase, stationary phase, detector, and computer for data acquisition. The mobile phase is a solvent or mixture of solvents pumped through the system under pressure. The stationary phase is a column made of either a polar (normal-phase) or nonpolar (reversed-phase) material, depending on the nature of the compounds to be separated. HPLC is optimal for small sample sizes and separates compounds based on their polarity, giving each compound a different affinity for the mobile and stationary phases and causing the compounds to pass through the column at different rates. Compounds are detected as they come off the column and go into the waste or are collected separately. Data is transmitted to the computer, creating a chromatograph. (Choice A) Gas chromatography requires small sample sizes but separates compounds based on boiling point. This method contains a stationary and mobile phase; however, the mobile phase is a gas rather than a solvent. (Choice B) Extraction separates compounds based on solubility in a particular solvent; this method uses two immiscible solvents that make up the aqueous and organic layers. No stationary phase, mobile phase, or detector is used in extraction. (Choice D) Thin-layer chromatography (TLC) separates small sample sizes and includes a stationary phase, solvent mobile phase, and detector (UV). However, TLC is not done under pressure. Educational objective: High-performance liquid chromatography is a purification technique that separates compounds based on polarity and consists of a mobile phase, stationary phase, detector, and computer for data acquisition. The mobile phase is a solvent or mixture of solvents that are pumped through the system under pressure, and the stationary phase is a column made of either a nonpolar or polar material.

Which Separation Technique Is Optimal for Purification of Small Sample