Shaving cream is a unique material that consists of all three states of matter: solid, liquid, and gas. It is mainly soap and water which in a can with a gas that is compressed. When you spray the shaving cream you are releasing the gas with the soap water mixture which makes the foam. Here are a few fun elementary science activities that can be performed using shaving cream.
1) Molding the Cream
You will need: 1 bottle of shaving cream, 1 box of corn starch
Now try this:
1) Place into a large container 1 entire box of corn starch
2) Spray over the corn starch 1 entire can of shaving cream
3) Mix thoroughly until the mixture stiffens and feels like a fluffy dough
4) Mold the mixture into different shapes.
2) Hydrophilic vs. Hydrophobic Cream
You will need: 1 bottle of shaving cream, paper plate, card stock, water, food coloring, clear cup or glass, spray bottle full of water, toothpick
Now try this:
1) Fill a clear cup or glass with water 2/3 full
2) Spray shaving cream on top of the water until the cup is full
3) Carefully add a few drops of food coloring and observe
4) Spray water from spray bottle on top of the food coloring and observe
1) Spray enough shaving cream to completely cover a paper plate
2) Smooth the surface of the shaving cream to make as flat as possible
3) Delivering only one drop at a time, place 4 different colors in random locations on the shaving cream
4) Using a toothpick swirl the colors to make a unique design in the shaving cream (note the color movement)
5) Press a piece of card stock paper onto the top of the shaving cream over your colored creation.
6) Lift up and wipe off the excess shaving cream on the card stock paper and observe.
7) Spray water from spray bottle on top of the food coloring and observe
Shaving cream is both hydrophobic and hydrophilic because soap is one of the main ingredients. Material that is hydrophobic repels water (has a fear of water). Material that is hydrophilic attracts water (loves water). This behavior is found in soap, allowing for many different types of compounds to be brought into water and removed from the surface being cleaned. Because soap is hydrophilic and food color is primarily water, when food coloring is added the food color is pulled to throughout the shaving cream. And because soap is also hydrophobic a small layer of food color remains on top. When the card stock is placed on the food coloring it leaves the hydrophilic end of the soap and adheres to the paper which it is more attracted to.
When water is sprayed onto the small layer of food coloring remaining on top of the shaving cream, the shaving cream regains most of its original white coloring. This is because the water has an attraction for the food coloring, which is mostly water.
For more experiments: www.chemicalkim.com