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Lesson 6 of 10

Getting it back

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5 min

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Filtering cannot remove dissolved salt. The salt is still in the water. How can you get the salt back?

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Salty water sits in an open dish.
Step 1 of 4
  1. Salty water sits in an open dish.
  2. Warmth from the sun. Water turns into vapour.
  3. All the water drifts away.
  4. Salt is left behind in the dish.

The rule

You get the salt back by turning the water into vapour.

Leave salty water in a warm, open dish. Evaporation — water turning into vapour, a gas you cannot see. The dish is open, so the vapour can leave.

Salt does not turn into vapour this way. It stays in the dish as a solid.

The salt you get back matches the salt you put in.

Try the lab to finish this lesson.