SOAP BUBBLES: NOT JUST KIDS' STUFF!

Soap bubbles are part of our life, so often we ignore them. Kids play with them, so it’s kids’ stuff! In fact, soap bubbles have drawn the attention not only of children but also of chemists, physicists and mathematicians, some as great as Sir Isaac Newton. Soap bubbles are formed when air is trapped inside soap films, sandwiching a thin layer of water between two layers of soap molecules. The polar oxygen-rich hydrophilic end of the soap molecule is attached to water molecule and the nonpolar hydrocarbon chain hydrophobic end repels water (Katz, 2010; Pepling, 2003). Due to the presence of two layers of soap films, light gets reflected off the outer layer and the inner layer leading to constructive and destructive interference. Depending upon the thickness of the soap bubble and the angle of the incident light, soap bubbles display various colors. Sir Isaac Newton studied the interference colors of thin films and made calculations of thin film thickness (Hall, n.d.). He calculated the thickness of soap bubbles at their thinnest point to be 1/2500000 inch or 0.000001016 centimeter.