Bubbles never fail to fascinate children and adults alike. They glimmer in iridescence as they float on air. Although some may even wonder how they are formed, the science behind it is quite simple.
A bubble is a spherical layer of soap film that encloses air or gas. The film is composed of a thin sheet of water sandwiched between two layers of soap molecules. Each soap molecule has a hydrophilic end which is attracted to water and a hydrophobic end which repels it. Hydrophobic ends tend to move towards the surface and stay away from the hydrophilic layer. It will cause water molecules to break away from each other and decrease surface tension, causing a bubble formation.
A bubble is a spherical layer of soap film that encloses air or gas. The film is composed of a thin sheet of water sandwiched between two layers of soap molecules. Each soap molecule has a hydrophilic end which is attracted to water and a hydrophobic end which repels it. Hydrophobic ends tend to move towards the surface and stay away from the hydrophilic layer. It will cause water molecules to break away from each other and decrease surface tension, causing a bubble formation.
Bubbles do not last long usually and burst quickly when their outside layer evaporates. To make them last long, manufacturers came up with an ingenious solution by adding glycerin to the bubble solution. Glycerin, or glycerol, is a clear and viscous alcohol which is a byproduct of soap making process. It is an ideal additive to bubble mixture because of its ability to dissolve with water. When added, it delays the dehydration process by attracting water molecules and forming weak hydrogen bonds. Water will evaporate longer than the usual, making the bubble wall stronger.
Glycerin also gives flexibility to the soap film. When a film bends, soap molecules move around to smaller glycerin molecules, instead of other soap molecules. This bonding gives soap molecules more freedom of movement, making bubbles suppler. However, for glycerin to be able to pack in between soap molecules, bubble mixture should be prepared for hours before use.
