What method would you use to separate salt from seawater?

What method would you use to separate salt from seawater?

• A. Filtration
• B. Distillation
• C. Evaporation
• D. Chromatography

Answer: (C)

When a dissolved substance like salt is in water, you separate it by removing the water. Evaporation turns liquid water into vapor and leaves the non-volatile salt behind as a solid. As the water disappears, salt crystals form that you can collect. Filtration wouldn’t work here because the salt is dissolved, not a separate particle to be trapped. Chromatography isn’t suited for pulling an dissolved ionic compound out of water. Distillation could also separate the water from the salt, but evaporation is the simpler, practical method used to harvest solid salt from seawater.

When a dissolved substance like salt is in water, you separate it by removing the water. Evaporation turns liquid water into vapor and leaves the non-volatile salt behind as a solid. As the water disappears, salt crystals form that you can collect. Filtration wouldn’t work here because the salt is dissolved, not a separate particle to be trapped. Chromatography isn’t suited for pulling an dissolved ionic compound out of water. Distillation could also separate the water from the salt, but evaporation is the simpler, practical method used to harvest solid salt from seawater.