The temperature of hydrogen gas is such that electrons are excited by atomic collisions up to the n = 3 atomic energy levels. Emission lines from which spectral sequences result when electrons return to the ground state?
A)Paschen (IR), Balmer (visible), and Lyman (UV) series
B)Lyman (UV) series only
C)Balmer (visible) and Lyman (UV) series
D)Balmer (visible) series only

Question

Quizplus · Accepted Answer

When hydrogen gas is excited so that electrons are excited to the n=3 energy level, they can return to the ground state (n=1) by emitting photons of various wavelengths. The Balmer series corresponds to photons emitted by electrons returning from n=3 to n=2, while the Lyman series corresponds to photons emitted by electrons returning from higher energy levels, including n=3, to the ground state (n=1). Therefore, the spectral sequences resulting from the electrons returning to the ground state are the Balmer (visible) and Lyman (UV) series. The Paschen series corresponds to photons emitted by electrons returning from higher energy levels to n=3, but these photons are not emitted in this scenario as we are looking at electrons returning to the ground state. Therefore, option A is incorrect. Option B only includes the Lyman series, but the Balmer series is also present in this scenario. Therefore, option B is incorrect. Option D only includes the Balmer series, but the Lyman series is also present in this scenario. Therefore, option D is incorrect. This leaves us with option C, which correctly includes both the Balmer and Lyman series. Therefore, the answer is C.

The Temperature of Hydrogen Gas Is Such That Electrons Are