SUPERsaturated solutions!

We have been learning about the concept of solubility and different types of solutions based on the amount of solute dissolved.

Today we did a lab experiment where we created unsaturated, saturated, and supersaturated solutions!

The solute we used was sodium thiosulfate.

We first dissolved a small amount of solute in water to create an unsaturated solution, which looks somewhat clear with no undissolved solid.

Then we added more solute until the solution was saturated, as evidenced by the undissolved crystals on the bottom of the test tube.

Then we heated the mixture as the solubility of the sodium thiosulfate increases as the temperature increases.

 Finally, we cooled the test tube to reduce the solubility, and "disturbed" the solution by adding a single additional crystal of the solute. The excess solute crystallized out in a dramatic fashion!