Shaving Cream and Food Coloring Chemistry

Decorate wrapping paper or eggs while illustrating scientific concepts and making real-world connections.

Foam shaving cream is primarily composed of air and soap. Soap is an amphipathic substance, which means that its molecules have both a hydrophilic (water loving) and a hydrophobic (water fearing) end. Because of this, soap is able to combine with water and with many oils.

When you drop food coloring (a hydrophilic substance) onto shaving cream, the cream’s hydrophobic end prevents the coloring from spreading. Use the technique to create a marble effect on paper for stationery or gift wrap or to decorate eggs.

Paper is primarily composed of cellulose (a hydrophilic substance). When you place paper on top of the shaving cream and the colored pattern, the food coloring is attracted to the paper, causing the colored pattern to transfer permanently to the paper.

Topics covered: properties of water, polarity, properties of soap.

Food coloring and dyed eggs or paper can stain hands, clothing, upholstery, and wood. To prevent staining your hands with food coloring, use disposable gloves.

Materials (per student)

  • Foam Shaving Cream

  • Liquid Food Coloring

  • Waxed Paper

  • Ruler

  • Toothpicks

  • Paper or Card Stock

Procedure

  1. Spread out the waxed paper so it covers an area slightly larger than the paper you are going to marble.

  2. Squirt shaving cream on the waxed paper and smooth it out with a ruler so that you have at least 2 cm of shaving cream covering the paper.

  3. Place drops of the food coloring that you like on the shaving cream.

  4. Using toothpicks, swirl the colors around in the shaving cream to create a desired pattern.

  5. Place the paper on top of the shaving cream so that it is lying flat. Pat it very lightly to ensure that the entire surface of the paper contacts the shaving cream.

  6. Grab the paper by a corner and peel the paper up from the shaving cream.

  7. Lay the paper flat on a dry surface with the shaving cream side up.

  8. Allow the shaving cream to dry.

  9. Using the ruler, scrape any remaining shaving cream from the paper.

A similar marbling technique can be used to decorate eggs.

This procedure can easily be modified to work when coloring eggs. Use a disposable pie pan or similar container with high sides to contain the shaving cream. When you place the egg on top of the shaving cream, the colored pattern created by the food coloring adheres to the egg. (A plastic spoon is helpful when transferring the egg.)

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