Objective
To demonstrate and understand the concept of supersaturation by creating a supersaturated solution and initiating crystallization.
Hypothesis
If a solution is heated, it can dissolve more solute than it can at room temperature, leading to a supersaturated state. When the solution cools or a seed crystal is introduced, rapid crystallization will occur.
Materials
- Soluble salt (e.g., Sodium Acetate or Sugar)
- Distilled water
- Beaker or saucepan
- Heat source (stovetop or hot plate)
- Spoon or stirring rod
- Thermometer
- Refrigerator or a cool place
- Seed crystals of the salt
- Safety goggles
- Gloves
Procedure
- Prepare a saturated solution of the salt in water, then heat this solution to create a supersaturated solution.
- Allow the solution to cool slowly to room temperature without disturbing it.
- Introduce a seed crystal to initiate crystallization.
Observations and Results
Document the changes during the cooling process and the rapid formation of crystals upon introducing the seed crystal.
Conclusions
Analyze how temperature affects the solubility of the salt and the role of seed crystals in crystallization in supersaturated solutions.
Safety Precautions
- Wear safety goggles and gloves when handling hot solutions and chemicals.
- Be cautious with the heat source to prevent burns.
Extensions
Consider repeating the experiment with different solutes or exploring the effect of different cooling rates and seed crystals on crystallization.