# Wave Function for Hydrogen

1. Feb 13, 2009

### jg370

1. The problem statement, all variables and given/known data

Suppose a hydrogen atom is in the $$2s$$ stat, with its wav function given by:

$$\psi_2_s (r) = \frac{1}{4\sqrt(2\pi a_o^\frac{3}{2})} (2-\frac{r}{a_o}) e^(-\frac{r}{2a_o})$$

Taking $$r = a_o$$, calculate $$\psi_2_s (a_o)$$

2. Relevant equations

3. The attempt at a solution

Since $$r=a_o=0.0529 nm$$, I get $$\frac{1.57*10^(14)}{ m^3}$$

Now, my question is "what is the meaning of this value?
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Feb 15, 2009

### Redbelly98

Staff Emeritus
Well, the units of a 3-D wave function should have m3/2 in the denominator (i.e. the units are m-3/2).

I'm not sure people actually ascribe physical meaning to the value of a wavefunction. I think of wavefunctions as a calculational tool in determining observable quantities such as position, momentum, energy, etc. QM is all about measurable quantities or observables.

Hope that helps.