To address this question, comprehension of adsorption principles and the methods presented in the options is necessary.
Adsorption Principle: Adsorption occurs when atoms, ions, or molecules of a substance (typically a gas, liquid, or dissolved solid) attach to the surface of an adsorbent. This phenomenon is fundamental to various purification techniques, wherein substances are selectively retained on the adsorbent material's surface.
An assessment of each option follows:
Extraction: This separation technique utilizes a solvent to isolate a substance from a mixture. It is not primarily dependent on adsorption.
Chromatography: This method separates mixture components by exploiting their differential migration rates through a medium driven by a solvent. Adsorption is a critical principle, as varying affinities of substances to the stationary phase lead to their separation.
Distillation: This technique separates mixtures based on the differing volatilities of components in a boiling liquid. It does not involve adsorption.
Sublimation: Sublimation is the direct transition of a solid to a gas phase, bypassing the liquid state. Adsorption is not a factor in this process.
Conclusion: Of the options provided, Chromatography is the purification method that employs the principle of adsorption. Separation and purification are achieved as the stationary phase in chromatography adsorbs mixture components to varying degrees.
