Since Sam's interest is in cosmetics, I am starting a unit on human skin, the anatomy and physiology of the skin. As we are progressing, I am stressing the importance of the physiology of the skin as regards her main interest. The term cutaneous was introduced as well as the main functions of the skin: immunity, prevention of dehydration, insulation, temperatue regulation and sensation. I discussed and outlined the improtance of each function as we listed them, as well as the evolutionary development of each function. The term pigmentation was developed and discussed in terms of variations among population and the need to incorporate the chemistry of pigmentation into products for cutaneous use. Using a diagram of the skin, we looked at the epidermis, defined the term and viewed the 5 structural layers which comprise this main layer of skin. Keratinization and desquamation were explained.

A quick review of Thursday's demonstrations led to a discussion of the principles of solubility. The definition of solubility was given and the term "like dissolves like" was put out for discussion. A sketch of the molecular structure of water was drawn as well as the molecular structures of methyl and ethyl alcohol. The production of these alcohols from fermentation was discussed. From the structural formulas of the alcohols and water, and the explanation of the OH group, we were able to elicit what is meant by like dissolves like. The meaning of saturated and supersaturated was arrived at using sugar dissolved in a given amount of water, and the application of heat to increase the solubility at a given volume- Rock Candy...

Using the lab room, we prepared a variety of mixture types. Homogenous solutions of salts, suspensions of solids in water and alcohol, emulsions of oil and water, with and without emulsifying agents. Sam would describe each physically and then I explained how the molecular particles interacted in each case.

Vlad took his Impulse-Momentum test.

See last written outline

Same lesson outline as last written

Same lesson outline as listed on previous session summaries. Sam has been absent

I had equipment and substances to be used to produce homogenous solutions, suspensions, emulsions and alcoholic solutions. The necessity to use different solvents will be determined and the pro's and con's of each discussed. This hopefully will lead into the formation of lotions, creams and ointments which can be applied to the skin and nails.

We used Sam's bottle of tea drink to review and reinforce the concepts of homogenous mixtures.
reading the ingredients label and discussing the solubility of each. The most common solvents were listed and the type of solution formed from water and alcohol discussed. The reason for the use of each was determined along with the drawback of using one solvent over another. Elixers and tinctures were talked about and the physical difference between them stressed.
Some less common solvent-solute mixtures were talked about and what they produce commercially and how they are used.

We reviewed for his test next week on the conservation of linear momentum.