Session S30a (Monday, 2pm, Osmond 119)

P217: How surfactants work

Aisling OConnor (Fitchburg State College, USA)

The goal of this demonstration is to illustrate how surfactants such as laundry detergent, dish soap, and shampoo work to dissolve oil and grease in water so that they can be rinsed away. Model surfactant molecules are created from small balls of blue play dough and bobby pins.  The play dough balls represent the hydrophilic heads of the surfactant molecules and the bobby pins represent the hydrophobic tails.  A yellow Styrofoam ball is used to represent a blob of oil or grease.  The action of a surfactant such as a shampoo is demonstrated by inserting the open (non-polar surfactant tails) ends of the bobby pins into the Styrofoam ball (oil / grease).  The blue play dough (polar surfactant heads) now surround the grease / oil and since the polar heads of the surfactant molecules dissolve in water, the ball of grease can be rinsed away!

Categories

A sample text widget

Etiam pulvinar consectetur dolor sed malesuada. Ut convallis euismod dolor nec pretium. Nunc ut tristique massa.

Nam sodales mi vitae dolor ullamcorper et vulputate enim accumsan. Morbi orci magna, tincidunt vitae molestie nec, molestie at mi. Nulla nulla lorem, suscipit in posuere in, interdum non magna.