Express the frequency in inverse seconds. n=4-->n=3. Can you please tell me what formulas to use, because I have like 6 more of these to do and I can't figure it out. Thanks.

Answer:
Explanation:
When an electron jumps from one energy level to a lower energy level some energy is released in the form of a photon.
The difference in energy between the two levels is the energy of the photon and that energy is related to the frequency of the photon by the Einstein - Planck equation:
Where,
So, to find the frequency you must first find the energy.
The transition energy can be calculated using the formula:
Where E₀ = 13.6 eV ( 1 eV = 1.602×10⁻¹⁹ Joules) and n = 1,2,3,...
So, the transition energy between n = 4 and n = 3 will be:
Now you can use the Einstein - Planck equation:
v = 1.597 x 10¹⁴ s⁻¹
Given:
Question:
Express the frequency in inverse seconds.
The Process:
To solve this problem, we will use the Planck-Einstein formula, which is:
[tex]\boxed{ \ E_1 - E_2 = hv \ }[/tex]
with,
where v represents the frequency of the emitted (radiated) photon.
And remember the ionization energy based on Bohr's theory, namely:
[tex]\boxed{ \ \Delta E = E_1 - E_2 = -13.6 \Big( \frac{1}{n_1^2} - \frac{1}{n_2^2} \Big) \ }[/tex] in eV (electronvolt).
[tex]\boxed{ \ 1 \ eV = 1.6 \times 10^{-19} \ joule \ }[/tex]
Step-1
[tex]\boxed{ \ E_1 - E_2 = -13.6 \Big( \frac{1}{4^2} - \frac{1}{3^2} \Big) \ }[/tex]
[tex]\boxed{ \ E_1 - E_2 = -13.6 \Big( \frac{1}{16} - \frac{1}{9} \Big) \ }[/tex]
[tex]\boxed{ \ E_1 - E_2 = -13.6 \Big( \frac{9 - 16}{144} \Big) \ }[/tex]
[tex]\boxed{ \ E_1 - E_2 = -13.6 \Big( - \frac{7}{144} \Big) \ }[/tex]
We got ΔE = 0.661 eV.
Let us convert eV to joules.
[tex]\boxed{ \ \Delta E = 0.661 \ eV \times 1.6 \times 10^{-19} \ \frac{J}{eV} \ }[/tex]
Thus, the energy emitted by photons from n = 4 to n = 3 is ΔE = 1.058 x 10⁻¹⁹ J.
Step-2
Now let us calculate the frequency of photons emitted during the transition.
[tex]\boxed{ \ hv = \Delta E \ } \rightarrow \boxed{ \ v = \frac{\Delta E}{h} \ }[/tex]
[tex]\boxed{ \ v = \frac{1.058 \times 10^{-19}}{6.626 \times 10^{-34}} \ }[/tex]
Thus, the frequency of photons emitted during the transition is [tex]\boxed{ \ v = 1.597 \times 10^{14} \ Hz \ }[/tex] or [tex]\boxed{ \ v = 1.597 \times 10^{14} \ s^{-1} \ }[/tex]