Determining atomic radius at home

[p.tryon]

I recall a physics teacher demonstrating an experiment where he transferred 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

 

[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.

 

[p.tryon]

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