How can ocean water be turned into fresh, usable water?

You will need:

Distilled water

Spoon, tape and ruler

Small clear, clean glass or cup


Marking pen

Large clear bowl

Plastic wrap

A marble or a clean rock

Perform the Experiment:

Fill the cup 3/4 full of distilled water.

Add one heaping spoonful of salt to the water and stir for 3 minutes.

Pour the salt water into a bowl.

Place the cup directly in the middle of the bowl. Cover the bowl tightly with plastic wrap and secure the plastic wrap with tape. DO NOT LET THE PLASTIC WRAP TOUCH THE CUP!

Place the marble on the plastic wrap and center it above the cup. Don't let this touch the cup either.

Place the bowl in the sunlight on a black background.

Observe and record the level of the salt water in the bowl each day for four days, marking the level with the pen.

Observe the water collecting on the plastic and dropping into the cup.

Each day, tap the marble lightly to collect more water in the cup.

On the fifth day, remove the plastic wrap and taste the water in the cup. Leave the uncovered bowl in the sun until all of the water evaporates and observe the remains in the bottom.
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