Science Fair Projects for Growing Epsom Salt Crystals

Crystals and Elements

• Crystals are made up of atoms, which are the building blocks of life. Atoms are made from smaller particles known as protons, or positively charged particles; electrons, or negatively charged particles; and neutrons, which have no charge. Each element is an atom with a particular structure, and when elements combine, they can form minerals. Salt is a mineral in crystallized form, and its atoms are organized in a cubic shape. Epsom salt is made of the elements magnesium, sulfur and oxygen, which form the compound magnesium sulfate.

Materials

• To effectively grow Epsom salt crystals, you need a few basic items you likely have in your home. Epsom salt is the most important ingredient, but you also need water, a pan for heating the water, and a plastic or paper cup. If you want to grow the crystals on a string rather than the side of the cup, you also require a string, such as yarn, a pencil and a metal washer. Growing the crystals on the string usually gives you larger and more evenly shaped crystals.

Procedure

• To grow your crystals, first boil about a half cup of water in a pan. Pour about 1 cup of Epsom salt into the water and stir until the salt dissolves. Continue to add more salt until it will no longer dissolve. Allow the water to cool to room temperature and pour the water into a cup. Leave the cup undisturbed for a few days; check back and you will see salt crystals have formed on the side of the cup. To use the string method, follow the same steps to dissolve the salt. Pour the salt water into a cup. Tie one end of the string around a pencil and tie a metal washer to the other end of the string. Place the string and washer in the water with the pencil lying on the top rim of the cup. The washer acts as a weight for the string.

Significance

• To follow the scientific method, you must also come up with a hypothesis that is tested by the procedure. You must follow up the experiment with results and conclusions. For example, hypothesize that salt crystals grow in a different shape than sugar crystals. Grow both kinds of crystals and compare the shapes; salt grows in cubic form, and sugar forms a hexagonal shape, which is based on the arrangement of the atoms. Investigate whether or not the kind of water you use to dissolve the crystals makes a difference: Does tap water or distilled water provide a different size of shape of crystal? Present your results and do some research on salt and crystals to determine the reasons for your experiment's outcome.