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Determining atomic radius at home

  1. Feb 16, 2010 #1
    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?

  2. jcsd
  3. Feb 16, 2010 #2
    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.
  4. Feb 17, 2010 #3
    Thanks. I have tried it but no luck so far... :-)
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