Quantum Mechanics Solution Manual 

© Leon van Dommelen 

4.3.4.1 Solution hydda
Question:
At what distance from the nucleus does the square of the ground state wave function become less than one percent of its value at the nucleus? Express it both as a multiple of the Bohr radius and in Å.
Answer:
The square wave function is
and the value at the nucleus 0 is then
For the value at above to be one percent of this, you must have
or taking logarithm, 2.3 . Expressed in Å, 0.53 Å, so 1.22 Å.