Answer:
Wavelength, [tex]\lambda=9.75\times 10^{-8}\ m[/tex]
Explanation:
We need to find the the wavelength of the light emitted by a hydrogen atom during a transition of its electron from the n = 4 to the n = 1 principal energy level. The energy is given by :
[tex]\Delta E=E_1-E_4[/tex]
[tex]\Delta E=-2.18\times 10^{-18}(\dfrac{1}{n_f^2}-\dfrac{1}{n_i^2})[/tex]
[tex]\Delta E=-2.04\times 10^{-18}\ J[/tex]
The energy of a photon is given by :
[tex]E=\dfrac{hc}{\lambda}[/tex]
[tex]\lambda=\dfrac{hc}{E}[/tex]
[tex]\lambda=\dfrac{6.63\times 10^{-34}\times 3\times 10^8}{2.04\times 10^{-18}}[/tex]
[tex]\lambda=9.75\times 10^{-8}\ m[/tex]
So, the wavelength of the light emitted by a hydrogen atom during a transition of its electron from the n = 4 to the n = 1 principal energy level is [tex]\lambda=9.75\times 10^{-8}\ m[/tex]. Hence, this is the required solution.