- 1). Put the pot on the stove or fire. Do not turn the heat source on. Place the cup in the center of the pot with the rim facing upward. The top of the cup must be 1 inch below the rim of the pot, or the lid will not fit on.
- 2). Pour the sea water into the pot until three-quarters of the glass is underwater. Make sure no water splashes inside the cup or the experiment will be contaminated.
- 3). Turn the lid upside down so the handle or knob is facing the floor. Put the lid on top of the pot. The handle or knob should be directly above the cup.
- 4). Turn the heat source on. Boil the water on a low heat for 20 minutes. The water will evaporate, condense on the pot lid and drip into the glass. The salt crystals will form a layer on the bottom of the pot.