The ionisation energy of hydrogen is the energy needed to move the electron from
Correct answer: C. n equals 1 to infinity
- A. n equals 1 to n equals 2
- B. n equals 2 to n equals 1
- C. n equals 1 to infinity
- D. infinity to n equals 1
Explanation
Ionisation means removing the electron completely, so it must be raised from the ground state to the level where its energy is zero, which is n at infinity, and that requires 13.6 eV. Moving between two bound levels needs less energy and simply excites the atom. The energy released in the reverse process is emitted as a photon.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Atomic Spectra
Atoms emit or absorb light at specific wavelengths because electrons occupy quantized energy levels and change levels by absorbing or releasing photons. The topic covers emission and absorption spectra, spectral series, hydrogen’s line spectrum, energy-level transitions, and the relation between wavelength, frequency and photon energy.
Practise Atomic Spectra
356 free Atomic Spectra MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Atomic Spectra questions
An absorption spectrum is produced when
Bohr postulated that the angular momentum of an electron in an allowed orbit is
The Lyman series of hydrogen appears in which region of the spectrum?
The wavelength of the photon emitted in a transition depends on
A limitation of the Bohr model is that it
In a laser, light is produced by