{"id":5883,"date":"2017-03-29T21:10:42","date_gmt":"2017-03-29T21:10:42","guid":{"rendered":"http:\/\/demos.swarthmore.edu\/physics\/?p=5883"},"modified":"2024-01-19T19:10:41","modified_gmt":"2024-01-19T19:10:41","slug":"size-of-oil-molecule","status":"publish","type":"post","link":"https:\/\/demos.swarthmore.edu\/physics\/2017\/03\/size-of-oil-molecule\/","title":{"rendered":"Size of Oil Molecule"},"content":{"rendered":"

\"0329171626\"<\/a><\/p>\n

When droplet of olive oil (oleic acid) is placed on water, oil spreads out until oil layer is 1 molecule high.<\/p>\n

If the oil “spill” radius and the size of the\u00a0original droplet can be measured, one can estimate the length of the oil molecule.<\/p>\n

Volume of original droplet = volume of oil spill pancake.<\/p>\n

Use wire loop (diameter~1mm), to estimate volume of droplet (assume droplet is wafer, not sphere). Use calipers to measure.<\/p>\n

\"0329171616\"<\/a><\/p>\n

Dip loop in olive oil.<\/p>\n

\"0329171618\"<\/a><\/p>\n

Remove excess oil using paper towel.<\/p>\n

\"0329171621\"<\/p>\n

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.<\/p>\n

\"0329171617\"<\/p>\n

\"0329171620\"<\/a><\/p>\n

Dip tip of wire loop into water. Oil immediately spreads out to form circle (very cool to watch!).<\/p>\n

Measure diameter with ruler.\"0329171623\"<\/a><\/p>\n

Should get order-of-magnitude accuracy.<\/p>\n