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Science Project: Mining Salt Viewed: 4128
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Mining Salt

In some tropical areas, salt is not mined from the earth but rather the sea. See how it is done.

What You Need:

  • A piece of string
  • Salt
  • Tablespoon
  • A Nail or Paper Clip
  • A Small Jar
  • Hot Water
  • A Pencil

What To Do:

  • Fill the jar with hot water and stir in 1 tablespoon (15 ml) of salt at a time until the salt no longer dissolves. It will take about a tablespoon of salt for every ounce (30 ml) of water.
  • Attach the nail to one end of the string. Wrap the other end of the string around a pencil.
  • Rest the pencil on the edge of the jar and suspend the nail in the jar of salted water so it hangs down but does not touch the bottom.
  • Place the jar in a warm place

What Happened:

After a few days, the water dries up and salt crystals form on the string.

Why:

Water molecules slowly go into the air as water vapor. As the water evaporates from the salt water, the salt atoms draw close together, forming crystals. When the water is gone, the salt crystals remain.