5 lab crystals with epsom salts by k5V4cU


									                                              Growing Crystals Lab

Objective: To prepare a supersaturated solution and observe the production of crystals using Epsom salts
(Magnesium Sulfate)

Pre-Lab questions:
   1. What is a saturated solution?

   2. What is solubility?

   3. What is a supersaturated solution?

   4. Write the formula of Magnesium sulfate?

   5. What type of compound is Magnesium sulfate?

   6. Explain why magnesium sulfate can be dissolved in water.

Safety: Use goggles and aprons. Be careful. Use beaker tongs to handle the hot beaker. Work carefully with the
hot plate.

  Distilled water
  Graduated cylinder
  200 mL beaker
  56 g (approx.1/4 cup) of Epsom salts (magnesium sulfate) in a plastic cup
  Hot plate
  Stir rod
  Beaker tongs
  Piece of yarn
  Food coloring
  Petri dish, clear plastic cup

      1. Measure out 75mL of DI water using a graduated cylinder ( remember to read below the meniscus)
      2. Place the water into a beaker and heat it up on a hot plate until it reaches 70 oC approximately (use a
          thermometer to check).
      3. Remove the beaker from the hot plate. Be Careful! Use a beaker tongs.
      4. Add the Epsom salts stirring the solution very well until all the salt has been added and dissolved.
          Note: The solution should be clear. If there still salt particles not dissolving heat it up again until all
          the salt has been dissolved.
      5. Add two drops of food coloring and stir again.
      6. Pour a small amount of the solution on a Petri dish (making just a thin film).
      7. Pour the rest of the solution in a plastic cup and add a piece of string to it. Label your cup and Petri
          dish, and place them on the window sill of your station.
      8. Clean your beaker, any used equipment, and your work area. Wash your hands.
Observations and questions;
  1. Observe the shape of the Epsom salts crystals before the dissolution in water and after the
      crystallization (24 hours later) and compare the shape and the size of the crystals.

   2. How did you know that the solution was saturated?

   3. How were you able to prepare a supersaturated solution?

   4. Which factors affected the rate of solvation of the Epsom salts in water?

   5. Why did the solution in the Petri dish crystallize faster than the one in the plastic cup?

   Your Lab report must include every part of the experiment for full credit:
   1. Title

   2. Objective of the lab

   3. Pre lab-questions and answers

   4. Summary of the procedure

   5. Observations & post-lab questions with answers

   6. Conclusion explaining what happened during the lab and what you learned!

To top