Take the size of a Rydberg atom to be the diameter of the
Chapter 41, Problem 41.71(choose chapter or problem)
Take the size of a Rydberg atom to be the diameter of the orbit of the excited electron. If the researchers want to perform this experiment with the rubidium atoms in a gas, with atoms separated by a distance 10 times their size, the density of atoms per cubic centimeter should be about (a) 105 atoms>cm3; (b) 108 atoms>cm3; (c) 1011 atoms>cm3; (d) 1021 atoms>cm3.
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