Experiments to Try at Home from the Cosmetics Topic Week

Cosmetics include many things, such as skin care, for example.

The skin, we are always told, is our biggest organ. But do you know how big your skin actually is? This experiment can give you the answer. Ask a friend if he or she would like to help you.

How large is the surface area of the skin?

For this experiment, you will need:

  • A partner
  • 1-2 rolls of toilet paper
  • 1 roll of masking tape

To determine the surface area of our skin, a test subject is wrapped in toilet paper.

  1. The test subject first puts their left foot on the start of the toilet paper. Carefully wrap the toilet paper around their left leg up to their hips and then back down their right leg. Tear off the toilet paper and put the end under their right foot.
  2. Fasten the new start of the toilet paper to the test subject’s pants using masking tape and wrap the toilet paper up to their chest. At one shoulder, wrap the toilet paper down one arm until you reach the hand. Then tear off the toilet paper again. The test subject holds the end of the toilet paper with their hand.
  3. Put the new start of the toilet paper in the test subject’s other hand. Wrap it up their other arm and around their shoulders and neck until you reach their head. Be very careful when you are wrapping the shoulders and head as the toilet paper tears easily here.
  4. Now carefully remove the toilet paper.
  5. Lay out the toilet paper on the prepared squares.

One square is as large as one square meter (12 square feet). How many square meters (or square feet) of skin does your test subject have?

The effect of cream

Have your parents ever applied cream to your face even though you didn’t want them to? And have you ever wondered why?

Materials needed for each group of two:

  • 2 freezer bags
  • Petroleum jelly (e.g. Vaseline)
  • 2 hair bands

Work with a partner.

  1. The test subject washes both hands thoroughly with soap.
  2. Pull a rubber hair band over the test subject’s right and left wrists (one on each wrist).
  3. Apply some petroleum jelly (e.g. Vaseline) to the test subject’s right hand. Do not apply anything to their left hand.
  4. Put both hands into freezer bags and seal the bags with the hair bands so that no air can get in. Make sure that as little cream as possible gets onto the freezer bag.
  5. Observe the test subject’s hands for five minutes and compare them. What happens to the freezer bags?