Silica gel and activated alumina are commonly implemented as __________________?
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Answer: B. Stationary phase
Explanation
Silica gel and activated alumina serve as stationary phases in various chromatography techniques. These porous solid materials remain fixed inside columns or plates while another phase moves past them. Polar compounds adsorb strongly onto their surfaces, achieving effective separation of complex chemical mixtures. Chromatography relies on the distribution of sample components between a stationary and a mobile phase. Silica gel possesses numerous surface hydroxyl groups that interact strongly with polar analyte molecules. Activated alumina is another metal oxide adsorbent used when different selectivity profiles are required.
Thin-layer and column chromatography are indispensable techniques for purifying synthetic organic reaction products. Biochemists use these stationary phases to isolate proteins, lipids, and nucleic acids in research laboratories. Optimizing stationary phase selection ensures high resolution and purity in analytical separations. Mobile phase refers to the moving solvent or gas carrying the sample through the system. Mixed phase describes combined solvent systems rather than the specific solid adsorbent materials used. Single phase implies a uniform homogeneous mixture rather than a heterogeneous chromatographic setup.
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Answer: D. crystallization
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Answer: C. Lunar Caustic
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Answer: C. Halides
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Answer: A. Aldehydes
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Answer: C. In b/w true solution & suspension
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Answer: B. Alkali
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