The wave functions for the 1s and 2s orbitals are as follows:

   1 s   ψ       =       ( 1 / π ) 1 / 2     ( 1 / a 0 3 / 2 )       exp   ( − r / a 0 )

   2 s   ψ       =       ( 1 / 32 π ) 1 / 2     ( 1 / a 0 3 / 2 )       exp   ( 2     −     r / a 0 )       exp   ( −     r / a 0 )

Where,
a 0 is a constant ( a 0 = 53 pm) and r is the distance from the nucleus. Use a spreadsheet to make a plot of each of these wave functions for values of r ranging from 0 pm to 200 pm. Describe the differences in the plots and identify the node in the 2s wave function.