# Problem: An excited hydrogen atom emits light with a wavelength of 397.2 nm to reach the energy level for which n = 2. In which principal quantum level did the electron begin?

###### FREE Expert Solution
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###### FREE Expert Solution

We’re being asked to determine in which principal quantum number level (or energy level, n) did the electron begin.

We’re going to use the Balmer Equation which relates wavelengths to a photon’s electronic transitions.

$\overline{)\frac{\mathbf{1}}{\mathbf{\lambda }}{\mathbf{=}}{{\mathbf{RZ}}}^{{\mathbf{2}}}\left(\frac{\mathbf{1}}{{{\mathbf{n}}^{\mathbf{2}}}_{\mathbf{final}}}\mathbf{-}\frac{\mathbf{1}}{{{\mathbf{n}}^{\mathbf{2}}}_{\mathbf{initial}}}\right)}$

λ = wavelength, m
R = Rydberg constant = 1.097x107 m-1
Z = atomic number of the element
ninitial = initial energy level
nfinal = final energy level

Calculate the initial principal quantum level (ninitial):

91% (332 ratings)
###### Problem Details

An excited hydrogen atom emits light with a wavelength of 397.2 nm to reach the energy level for which n = 2. In which principal quantum level did the electron begin?

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Bohr and Balmer Equations concept. If you need more Bohr and Balmer Equations practice, you can also practice Bohr and Balmer Equations practice problems.

What is the difficulty of this problem?

Our tutors rated the difficulty ofAn excited hydrogen atom emits light with a wavelength of 39...as medium difficulty.

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What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor McCrory's class at UMICH.

What textbook is this problem found in?

Our data indicates that this problem or a close variation was asked in Chemistry: An Atoms First Approach - Zumdahl Atoms 1st 2nd Edition. You can also practice Chemistry: An Atoms First Approach - Zumdahl Atoms 1st 2nd Edition practice problems.