Atomic structure and determing effective nuclear charge

1. Oct 29, 2008

joker314

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

The 3s state of Na has an energy of -5.14 eV. Determine the effective nuclear charge.

2. Relevant equations

Zeffective = Z - S (not listed in text book, found this online when trying to figure out the problem)

3. The attempt at a solution

Nothing in the text book in this section talk about determining nuclear charge. I know that Na is in the 2s$$^{2}$$2p$$^{6}$$ group.

2. Oct 29, 2008

olgranpappy

For a hydrogenic atom, what is the expression for the energy-levels in terms of the principle quantum-number?

3. Oct 29, 2008

joker314

I believe that would be 1s

4. Oct 30, 2008

olgranpappy

no. you need an equation that relates energy "E" to the principle quantum number "n". Do you know an equation like that?

5. Nov 8, 2008

joker314

I do now... Even though I read that response too late. The grader of my homework gave me full credit anyways for a sub-par result.... But I appreciate the response because it let me on the right track after the fact!