(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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

2. Relevant equations

I believe you have to use:

En=-[(13.6eV)Zeff^2]/n^2

3. The attempt at a solution

So since Na is in the 3s state, I think n=3. So:

-5.14eV= -[(13.6eV)Zeff^2)]/9

-46.3eV=(-13.6eV)Zeff^2

Zeff=sqrt(3.40)=1.85

However the answer in the back of the book is giving me 1.14e, could someone show me my mistake?

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# Determining effective nuclear charge

Can you offer guidance or do you also need help?

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