Skip to main content
Ch.5 - Periodicity & Electronic Structure of Atoms

Chapter 5, Problem 124

Orbital energies in single-electron atoms or ions, such as He+, can be described with an equation similar to the Balmer–Rydberg equation:

where Z is the atomic number. What wavelength of light in nanometers is emitted when the electron in He+ falls from n = 3 to n = 2?

Verified Solution
Video duration:
1m
This video solution was recommended by our tutors as helpful for the problem above.
698
views
Was this helpful?

Video transcript

Hey everyone, we're told an equation resembling the Balmer Rydberg equation shown below where Z is the atomic number? Can be used to describe the orbital energies of single electron atoms or ions such as lithium. What wavelength of light and nanometers is released? When the electron in lithium falls from N equals four to n equals two. First. Let's recall our Rydberg constant which is going to be 1.97 times to the negative two nanometers to the negative first. And since our lithium falls from N equals forward to N equals two, this means R N final is going to be two and R N initial is going to be four. And when we look at our periodic table, the Z. Which is our atomic number of lithium is going to be three. Now let's go ahead and plug in our values. So we have one over our wavelength equals Z squared, which is three squared times are right for constant and nanometers times one over NF squared, which will be two squared -1 over an initial squared, which is going to be four squared. When we calculate this out, we end up with a one over wavelength of 0. nanometers to the negative first, Converting this into our wavelength, we end up with 54.0194 nm and this is going to be our final answer. Now I hope that made sense. And let us know if you have any questions
Related Practice
Textbook Question
Fill in the blanks with the appropriate region of electromagnetic radiation: UV, visible, infrared. (a) The Sun most strongly emits in the _____ and regions of electromagnetic radiation (b) The atmosphere filters out biologically damaging ______ radiation from incoming solar radiation and prevents it from reaching Earth. (c) The Earth most strongly emits ______ radiation. (d) Greenhouse gases absorb _______ radiation.
1272
views
Textbook Question

Order the following atoms according to increasing atomic radius: Rb, Cl, As, K.

1099
views
Textbook Question
Why do the Earth and Sun have different emission spectra?
645
views
Textbook Question

Imagine a universe in which the four quantum numbers can have the same possible values as in our universe except that the angular-momentum quantum number l can have integral values of 0, 1, 2...n + 1 (instead of 0, 1, 2..., n - 1). (a) How many elements would be in the first two rows of the periodic table in this universe?

1637
views
Textbook Question

Imagine a universe in which the four quantum numbers can have the same possible values as in our universe except that the angular-momentum quantum number l can have integral values of 0, 1, 2...n + 1 (instead of 0, 1, 2..., n - 1). (c) Draw an orbital-filling diagram for the element with atomic number 12.

384
views
Textbook Question
One watt (W) is equal to 1 J/s. Assuming that 5.0% of the energy output of a 75 W light bulb is visible light and that the average wavelength of the light is 550 nm, how many photons are emitted by the light bulb each second?
912
views
1
rank