News Archive Item
Potions & Lotions
Description:
For this activity we brought college-level science into an elementary school classroom to celebrate this year’s Chemists Celebrate Earth Day theme “Rethinking Recycling: It’s Easy to be Green.” Keck Science students Isabel English (Scripps College) and Carmen Velazquez (Pitzer College) drafted a script of age-appropriate language, describing processes occurring at the molecular level when an emulsion is formed. Emily Muller (Scripps College) created a large poster as a visual aid based on our handouts. Keck Science provided glassware, hot plates, and stirring rods. Elementary school students and teachers brought recycled Easter eggs and used egg containers for the balm. Brandon Kim (Pitzer College) and Moriah Lerner (Scripps College) facilitated this activity for about one-hundred 5th graders, according to color-coded recipe cards they made. This effort was coordinated by a teacher from Salinas Elementary named Brian Zubak. Lily Rubin (Pitzer College) assisted in obtaining the organic ingredients from local Great Earth Vitamin Store, Rite Aid, and Whole Foods. The 5th grade students got to take home Almond Honey Lip Balm, Cocoa Mint Lip Balm, or Vanilla Lip Gloss, one was made with the students’ help on each of 3 tables. Some of them suggested that they would give it to their mom for the upcoming Mother’s Day.
Our second activity was more on the theoretical side of emulsions. We had students from the 3 tables find others in the cafeteria that were wearing the same color of gloves that they had. This represented our starting conditions when we had our ingredients for the recipes separated. Some students had two purple gloves, some students had two yellow gloves, some students had one of each. We called the purple people “hydrophobic” molecules and the yellow people “hydrophilic” molecules and the people who had one glove of each color were called “surfactant” molecules. We turned up the temperature on the imaginary hot plate so every molecule had to start moving faster! When they cooled (slowed) back down, we found out why the emulsion has the texture that it does, because the surfactants had brought hydrophobic and hydrophilic molecules together. By the time this activity was completed, the real lip balm had solidified and the lip gloss remained a slurry texture.
Our wrap-up activity gathered a small group of students around some plants (fennel, chard, spinach, and parsley) in recycled 2 L plastic soda bottles, left over from a general chemistry water quality lab at the college. As we all tried the lip balms we had made, we discussed how many cosmetics now contain botanical ingredients which can be extracted from living plants! Students smelled, touched, and tasted the herbs and compared them with the texture and aroma of their newly made “green cosmetics.” This activity was inspired by T. Joseph Lin (who developed low-energy emulsification while working at Max Factor Cosmetics for 20 years) who shared his career retrospective at the January 2012 American Chemical Society local section meeting. He emphasized that the market for green cosmetics is projected to increase, making ‘Potions & Lotions’ an attractive career for young scientists. These plants are still growing in the student garden at school and the balms are still quite stable in a drawer in my office.
