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Old 15th Jul 2004, 08:47
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bookworm
 
Join Date: Aug 2000
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Couple a numbers for you. You get avogadro's number of gas molecules in the standard molar volume. That's 6 x 10^23 molecules per 22.4 litres (2.24x 10^-2 m^3).

So the volume per molecule is 2.24x 10^-2 m^3/ 6 x 10^23 or about 3 x 10^-26 m^3. If you divide that up per molecule, it's about a 30 angstrom sided cube.

A nitrogen molecule has a bond length of about an angstrom.

So it really doesn't make much difference if the bond stretches a bit. In fact, it doesn't make much difference what length the bond is at all! -- the molecular volume of gases is the same, as their molecular speed distribution only really depends on the temperature.
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