Lyman series, hydrogen

Procedure. Use Mathcad, QLLSQ, or TableCurve (or, preferably, all three) to determine a value of the ionization energy of hydrogen from the wave numbers in Table 3-4 taken from spectroscopic studies of the Lyman series of the hydrogen spectrum where ni = 1. 

Table 3-4 Spectral Wavenumbers v for the Lyman Series of Hydrogen...

It is possible to change the conditions in the helium discharge lamp so that the helium is ionized predominantly to He (He II). The radiation is due mainly to the n = 2 — n = transition of He II (analogous to the first member of the Lyman series of the hydrogen atom in Figure 1.1) at 30.4 nm with an energy of 40.81 cY A thin aluminium foil filter can be used to remove any He I radiation. 

Lyman series A series of lines in the spectrum of atomic hydrogen in which the transitions are to orbitals with n = l. 

The discovery of two other series of emission lines of hydrogen came later. They are named for their discoverers the Lyman series in the ultraviolet range and Paschen series in the infrared region. Although formulas were devised to calculate the spectral lines, the physics behind the math was not understood until Niels Bohr proposed his quantized atom. Suddenly, the emission spectrum of hydrogen made sense. Each line represented the energy released when an excited electron went from a higher quantum state to a lower one. 

Eventually, other series of lines were found in other regions of the electromagnetic spectrum. The Lyman series was observed in the ultraviolet region, whereas the Paschen, Brackett, and Pfund series were observed in the infrared region of the spectrum. All of these lines were observed as they were emitted from excited atoms, so together they constitute the emission spectrum or line spectrum of hydrogen atoms. 

Although we have not yet described the modem methods of dealing with theoretical chemistry (quantum mechanics), it is possible to describe many of the properties of atoms. For example, the energy necessary to remove an electron from a hydrogen atom (the ionization energy or ionization potential) is the energy that is equivalent to the series limit of the Lyman series. Therefore, atomic spectroscopy is one way to determine ionization potentials for atoms. 

Lyman series The series of the hydrogen atom spectrum with n = 1 as the starting level. 

Lyman-alpha radiation spect Radiation emitted by hydrogen associated with the spectral line in the Lyman series whose wavelength is 121.5 nanometers. iT-man al-fo, rad-e a-sh3n ... 

Lyman limit spect The lower limit of wavelengths of spectral lines in the Lyman series (912 angstrom units), or the corresponding upper limit in frequency, energy of quanta, or wave number (equal to the Rydberg constant for hydrogen). iT-mon, lim-3t ... 

Lyman series spect A group of lines in the ultraviolet spectrum of hydrogen covering the wavelengths of 121.5-91.2 nanometers. iT-mon, sir-ez lyonium ion chem The cation that is produced when a solvent molecule is protonated. iT an-e-om, T-3n ... 

This equation was discovered by Balmer in 1885.7 These speotral lines constitute the Balmer series. Other series of lines for hydrogen correspond to transitions from upper states to the state with n = 1 (the Lyman series), to the state with n = 3 (the Paschen series), and sp on. 

Subsequent to the discovery of the Balmer series of lines in the visible region of the electromagnetic spectrum, it was found that many other spectral lines are also present in nonvisible regions of the electromagnetic spectrum. Hydrogen, for example, shows a series of spectral lines called the Lyman series in the ultraviolet region and still other series (the Paschen, Brackett, and Pfund series) in the infrared region. 

What are the two longest-wavelength lines (in nanometers) in the Lyman series of the hydrogen spectrum ... 

PROBLEM 5.7 What is the energy (in kilojoules per mole) of photons corresponding to the shortest-wavelength line in the Lyman series for hydrogen (Worked Example 5.3) ... 

What is the energy difference (in kilojoules per mole) between the first and second shells of the hydrogen atom if the first emission in the Lyman series occurs at A = 121.5 nm ... 

Eventually, this series of lines became known as the Balmer series. Balmer wondered whether his little formula might be extended to study the spectra of other elements. He knew similar patterns exist in the line spectra of many elements. He also wondered about spectral lines that the human eye can t see. A few years later, in 1906, additional series of lines were in fact discovered for hydrogen in the ultraviolet region of the spectrum. These were called the Lyman series after their discoverer, Theodore Lyman. Other famous series are the Paschen series, named after German scientist Friedrich Paschen, the Brackett series, named after U.S. scientist F. S. Brackett, and the wonderful Pfund series, named after U.S. scientist August Herman Pfund. The Paschen, Brackett, and Pfund series lie in the infrared region. ... 

Lyman Series This series is formed when excited electrons in a hydrogen atoms fall from a higher energy level to first level. This series of lines is observed in ultraviolet region. 

As a result of his work, the lines in the visible spectrum are known as the Balmer series. The other series of lines in the atomic emission spectrum of hydrogen were discovered later (the next wasn t discovered until 1908). These series are named after the scientists who discovered them for example, the series in the ultraviolet region is known as the Lyman series after Theodore Lyman. 

Photons are emitted in the Lyman series as hydrogen atoms undergo transitions from various excited states to the ground state. If ground-state He are present in the same gas (near stars, for example), can they absorb these photons Explain. 

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