- #1

- 35

- 0

**1. Is a 4p -> 4s transition allowed in sodium? If so, what is the wavelength? If not, why not? (Z = 11 for sodium)**

**2. [tex]\Delta[/tex]l = |l2 - l1| = 1**

That is for the first question, in which case it is allowed, hence |0-1| = |-1| = 1, and meets the requirements for the equation.

The second part is what I don't understand because I used these equations:

[tex]E_{n}[/tex] = [tex]\frac{-13.60}{n^{2}}[/tex]eV

n = 1, 2, 3, ...

That is for the first question, in which case it is allowed, hence |0-1| = |-1| = 1, and meets the requirements for the equation.

The second part is what I don't understand because I used these equations:

[tex]E_{n}[/tex] = [tex]\frac{-13.60}{n^{2}}[/tex]eV

n = 1, 2, 3, ...

Next I used:

[tex]\Delta[/tex]E[tex]_{atom}[/tex] = E[tex]_{1}[/tex] - E[tex]_{2}[/tex] = 0

Meaning, I get zero for this because of the repeating n = 4, then 4[tex]^{2}[/tex] which = 16 and therefore I have an issue here I do not know how to solve after pondering.

The third equation I must use is:

[tex]\lambda[/tex] = 1240 eV nm / [tex]\Delta[/tex]E

But I am not there yet...

**3. As you can see my attempt is either erroneous or there is some sort of lone energy I am not aware of, by the way, the answer to this is:**

Yes; 2.21 [tex]\mu[/tex]m

Thank you.

Yes; 2.21 [tex]\mu[/tex]m

Thank you.