Surface Tension Lab
Surface tension in soap film causes the characteristic spherical shape of soap bubbles.Copyright 2004 Microsoft Corporation, One Microsoft Way, Redmond, WA 98052-6399 USA. All rights reserved.
Students extend their understanding of surface tension by exploring the real-world engineering problem of deciding what makes a "good" soap bubble. Student teams first measure this property, and then use this measurement to determine the best soap solution for making bubbles. They experiment with additives to their best soap and water "recipes" to increase the strength or longevity of the bubbles. In a math homework, students perform calculations that explain why soap bubbles form spheres.
Engineers design inkjet printers by exploiting the tendency of a continuous stream of water to break apart and form droplets. Surface tension must be finely adjusted, both for the ink to form droplets of the desired size and for the ink to adhere to the paper surface without smearing or bleeding, so part of the chemical engineering includes the "ink" formulation. Inkjet printers are also especially designed for many industrial applications, such as automotive coatings, decoration of curved and irregularly-shaped surfaces, printing conductive patterns with metallic particles, replacing screen printing on everything from ceramics to textiles, and creating rapid 3D prototypes.
After this activity, students should be able to:
- Describe the procedure developed to test the bubble mixtures, and explain how the procedure could be improved.
- Describe the criteria used to determine whether a solution created a "better" bubble, and explain how the criteria could be improved.