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The clectron in a hydrogen atom, originally in level n=9, undergoes a transition to a lower level by emitting a photon

of wavelength 384 nm. What is the final level of the electron?

c = 3.00 x 10 m/s,

h = 6.626 X 10^-34J-s,

Rh= 2.179 X 10^-18

1 Answer

6 votes

Step-by-step explanation:

The given data is as follows.


n_(1) = 9,
n_(2) = ?

Z for hydrogen = 1

As we know that,

Energy (E) =
(hc)/(\lambda)

where, h = planck's constant =
6.626 * 10^(-34) Js

c = speed of light =
3 * 10^(8) m/s


\lambda = wavelength

According to Reydberg's equation, we will calculate the energy emitted by the photon as follows.


\Delta E = -2.179 * 10^(-18) J * (Z)^(2)[(1)/(n^(2)_(2)) - (1)/(n^(2)_(1))]

or,
(hc)/(\lambda) =
-2.179 * 10^(-18) J * (Z)^(2)[(1)/(n^(2)_(2)) - (1)/(n^(2)_(1))]

Putting the given values into the above equation as follows.


(hc)/(\lambda) =
-2.179 * 10^(-18) J * (Z)^(2)[(1)/(n^(2)_(2)) - (1)/(n^(2)_(1))]


(6.626 * 10^(-34) Js * 3 * 10^(8)m/s)/(384 * 10^(-9) m) =
-2.179 * 10^(-18) J * (1)^(2)[(1)/(n^(2)_(2)) - (1)/((9)^(2))]

n = 2

Thus, we can conclude that the final level of the electron is 2.

User Maxwelll
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