Which of the following methods is most suitable for separating a mixture of sand and salt dissolved in water?

• A. Centrifugation
• B. Chromatography
• C. Filtration followed by evaporation
• D. Distillation only

Answer: (C)

Verified step by step guidance

1. Identify the components of the mixture: sand (solid, insoluble in water) and salt (soluble in water).
2. Understand that sand does not dissolve in water, so it can be separated by a physical method that removes solids from liquids, such as filtration.
3. Recognize that after filtration, the salt remains dissolved in the water (filtrate), so to recover the salt, the water must be removed.
4. Use evaporation to remove the water from the salt solution, leaving solid salt behind.
5. Evaluate other methods: centrifugation separates based on density but is less practical here; chromatography separates based on chemical properties and is unnecessary; distillation separates liquids based on boiling points but is more complex than evaporation for this case.