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Homework Help: Calculate average spacing of molecules

  1. May 13, 2008 #1
    1. The problem statement, all variables and given/known data

    CHCl3 has M= 119 gmol^-1, density (rho) = 1.48 gcm^-3
    Find the average separation between molecules in the liquid assuming a simple cubic packing

    2. Relevant equations

    3. The attempt at a solution

    I have found that there are 7.487x10^21 molecules cm^-3. Each molecule "occupies" a box of 133.6 Å^3. Now what should I do? I don't properly understand what they mean by separation.
  2. jcsd
  3. May 13, 2008 #2


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    Homework Helper

    Hi helpmeplease1,

    I believe by separation they mean the distance between nearest neighbors. If you think of the molecules as being in the center of the cubical box (whose volume you found), what's the distance between the center of two adjacent boxes?
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