The Lyman series corresponds to electronic transitions in a hydrogen atom from higher energy levels to the ground state (n=1). Because these transitions involve large energy changes, the emitted photons have high frequencies and short wavelengths, placing them squarely in the ultraviolet region of the electromagnetic spectrum.
15032
What type of emission spectrum is observed when light from a hydrogen-filled discharge tube is analyzed?
A hydrogen discharge tube contains low-pressure gas excited by an electric current. As excited electrons drop to lower energy states, they emit photons with specific, discrete energies. These discrete energies correspond to specific wavelengths, which appear as distinct lines on a spectrometer. This is known as an emission line spectrum, which is characteristic of atomic gases.
15033
Which of the following statements accurately describes the Paschen series in the hydrogen emission spectrum?
The Paschen series consists of discrete spectral lines produced when electrons in a hydrogen atom transition from higher energy levels (n > 3) to the third energy level (n=3). These transitions emit photons with wavelengths located in the infrared region of the electromagnetic spectrum.
15034
Which form of radiation is not produced during an electronic transition within an atom?
Electronic transitions involve electrons moving between energy levels within the electron cloud of an atom, resulting in the emission of photons in the infrared, visible, or ultraviolet ranges. Conversely, gamma (γ) rays are produced by transitions within the atomic nucleus itself, such as during radioactive decay or nuclear reactions. Therefore, gamma rays are not a product of electronic transitions.
15035
Which historical scientific investigation was responsible for analyzing the Fraunhofer lines found in the solar spectrum?
Robert Bunsen and Gustav Kirchhoff pioneered spectral analysis in the mid-19th century. By comparing the emission spectra of chemical elements with the absorption lines in the solar spectrum (Fraunhofer lines), they successfully identified the chemical composition of the Sun's atmosphere.
15036
In the Brackett series of the hydrogen spectrum, to which orbit do the electrons transition?
The spectral series of hydrogen are defined by the final energy level (n_final) of the electron transition. The Lyman series ends at n=1, Balmer at n=2, Paschen at n=3, and the Brackett series ends at n=4. Therefore, when an electron transitions from a higher energy level to the 4th orbit, it emits a photon corresponding to a line in the Brackett series.
15037
What is the approximate average lifetime of an excited atom before it returns to its ground state?
The spontaneous emission of a photon from an excited atom is a rapid process. Experimental measurements and quantum mechanical calculations indicate that the typical lifetime of an excited electronic state in an atom is on the order of 10^-8 seconds. This short duration reflects the high probability of the electron transitioning back to a lower energy state by emitting a photon.
15038
Which spectral series of the hydrogen atom is located within the ultraviolet region of the electromagnetic spectrum?
The Lyman series corresponds to electron transitions ending at the n=1 energy level. Because the energy gap between n=1 and any higher level is significant, the emitted photons have high energy and short wavelengths, placing them in the ultraviolet range. In contrast, the Balmer series falls in the visible range, while the Paschen, Brackett, and Pfund series fall in the infrared range.
15039
Which of the following radiations is not produced during an electronic transition within an atom?
Electronic transitions involve electrons moving between energy levels within the electron cloud of an atom, which typically results in the emission of infrared, visible, or ultraviolet photons. Gamma rays, however, are produced by transitions within the atomic nucleus itself, involving changes in nuclear energy states, and therefore cannot be produced by electronic transitions.
15040
What type of spectral pattern is observed when light from a hydrogen-filled discharge tube is analyzed?
A hydrogen discharge tube contains low-pressure gas excited by an electric current. As excited electrons return to lower energy states, they emit photons at specific, quantized frequencies. This results in a series of distinct, sharp lines known as a line spectrum. Unlike solids or dense gases that produce continuous spectra, atomic gases produce discrete lines corresponding to the energy transitions of their electrons.