Salt water, sand and iron filings, oil and water — all mixtures, but each needs a different trick to separate.
Different mixtures need different separation methods, depending on the properties of their components.
How would you separate sand from water?
By filtration — the sand (insoluble solid) stays on the filter paper while water passes through
How would you recover dissolved salt from salt water?
By evaporation — heating the water until it evaporates away, leaving the solid salt behind
Distillation separates liquids with different boiling points by heating and then condensing the vapour. Chromatography separates substances based on how differently they move through a medium, often used to separate dyes or pigments.
How does distillation separate two liquids mixed together, like water and alcohol?
Since the liquids have different boiling points, heating the mixture lets the lower-boiling-point liquid evaporate first, which is then condensed and collected separately
1. Which technique would you use to separate sand from water?
2. Which technique would you use to get salt back from salt water?
3. Which technique separates liquids based on differing boiling points?
4. Which technique is often used to separate the different dyes in ink?
5. Why can't filtration be used to separate salt dissolved in water?