Series Lyman

Lyman series See Balmer series, lyogels See xerogels. 

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) (Balmer Series) (Paschen Series)... 

All of the lines in the Balmer series (Table 6.1) come from transitions to the level n = 2 from higher levels (n = 3, 4, 5,. . . ). Similarly, lines in the Lyman series arise when electrons fall to the n = 1 level from higher levels (n = 2, 3, 4,. . . ). For the Paschen series, which lies in the infrared, the lower level is always n = 3. 

A line in the Lyman series (nio = 1) occurs at 97.23 nm. Calculate nu for the transition associated with this line. 

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. 

The ionisation energy of the H atom corresponds to removing the electron from the n = 1 energy level. Determine the convergence limit for the H Lyman series and hence estimate the ionisation energy of the H atom in kJ mol-1. 

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

B The longest wavelength light results from the transition that spans the smallest difference in energy. Since all Lyman series emissions end with nf= 1, the smallest energy transition... 

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 ... 

Figure 2.10 Response surface showing an inherently discrete response (number of lines in the Lyman series) as a function of an inherently continuous factor (excitation energy).

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. 

Lyman series, far ultraviolet. Paschen series, far infrared, Brackett series, far infrared, Pfund series, far infrared. 

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