In the context of chromatography, which statement best describes a chromatophilic substance in a neuron?

• A. It is a substance that does not interact with either phase and remains at the origin.
• B. It is a substance that is repelled by the stationary phase and elutes quickly.
• C. It is a substance that reacts chemically with the mobile phase to produce a colored product.
• D. It is a substance that has a strong affinity for the stationary phase and moves slowly during separation.

Answer: (D)

Verified step by step guidance

1. Understand the context: Chromatography is a technique used to separate components of a mixture based on their interactions with two phases — the stationary phase and the mobile phase.
2. Define chromatophilic substance: In chromatography, a chromatophilic substance is one that has a strong affinity for the stationary phase, meaning it tends to stick or bind to it rather than moving freely with the mobile phase.
3. Analyze behavior during separation: Because the chromatophilic substance interacts strongly with the stationary phase, it moves more slowly through the chromatographic system compared to substances that prefer the mobile phase.
4. Contrast with other options: Substances that do not interact with either phase remain at the origin; those repelled by the stationary phase elute quickly; and substances reacting chemically with the mobile phase to produce color are not described as chromatophilic.
5. Conclude that the best description of a chromatophilic substance in a neuron is one that has a strong affinity for the stationary phase and moves slowly during separation.