1. Feb 16, 2010

p.tryon

I recall a physics teacher demonstrating an experiment where he transfered a droplet of oil to the surface of water and carried out some calculations to determine the radius of a carbon atom. I was hoping to replicate the experiement- However I forget the details.

Has anyone seen this experiement and could explain the details? And/or direct me to a useful website?

Thanks
Pete

2. Feb 16, 2010

Stonebridge

The experiment used an oil drop of known volume that was assumed to spread itself out on the surface of the water such that it formed a layer one molecule thick.
Measuring the radius of this (circular) oil patch, and assuming it is in the form of a cylinder, gives the "length" of that cylinder, and an estimate of the molecular size. (FRom volume = length times area of cross section)
If the molecule consists of, say, a chain of 12 carbon atoms, you can estimate the size of one atom.

3. Feb 17, 2010

p.tryon

Thanks. I have tried it but no luck so far... :-)