Chemistry · Unit 2 · Intermolecular forces and gases · Intermolecular forces
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A student obtains a sample of liquid sweetener and performs thin layer chromatography (TLC) to determine whether it contains multiple dyes. The TLC plate is developed using an appropriate solvent system and examined under ultraviolet (UV) light. Two spots are observed at different positions on the plate. Which statement correctly explains what this result indicates?
Which observation from a thin layer chromatography (TLC) experiment would indicate that a substance is impure?
A chemist performs thin layer chromatography (TLC) on a sample of food colouring to determine its composition. The developed TLC plate shows three distinct spots with different Rf values. Identify what the chromatogram indicates about the composition of the food colouring sample, and state one reason why TLC is a suitable technique for this analysis.