![0329171626](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171626-300x169.jpg)
When droplet of olive oil (oleic acid) is placed on water, oil spreads out until oil layer is 1 molecule high.
If the oil “spill” radius and the size of the original droplet can be measured, one can estimate the length of the oil molecule.
Volume of original droplet = volume of oil spill pancake.
Use wire loop (diameter~1mm), to estimate volume of droplet (assume droplet is wafer, not sphere). Use calipers to measure.
![0329171616](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171616-169x300.jpg)
Dip loop in olive oil.
![0329171618](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171618-169x300.jpg)
Remove excess oil using paper towel.
![0329171621](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171621-300x169.jpg)
Dust surface of water with lycopodium powder. This allows you to see clearly the final diameter of the spill. The larger the container the better.
![0329171617](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171617-169x300.jpg)
![0329171620](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171620-300x169.jpg)
Dip tip of wire loop into water. Oil immediately spreads out to form circle (very cool to watch!).
Measure diameter with ruler.![0329171623](http://demos.swarthmore.edu/physics/wp-content/uploads/sites/2/2017/03/0329171623-300x169.jpg)
Should get order-of-magnitude accuracy.
- Lycopodium powder and oil located in L35, corrosive materials cabinet (powder is safe to handle).
- Tub located in L35.
- Calipers located in L35, section D-2.
- Tape measure in L35, section A-1.