Q27.A doubly ionised Li atom is excited from its ground state(n = 1) to n = 3 state. The wavelengths of the spectral lines are given by λ32, λ31 and λ21 . The ratio λ32/λ31 and λ21/λ31 are, respectively (1) 8.1, 0.67 (2) 8.1, 1.2 (3) 6.4, 1.2 (4) 6.4, 0.67
What This Question Tests
This question involves applying the Rydberg formula or energy level calculations for a hydrogen-like atom (doubly ionized Lithium) to determine the wavelengths of different spectral lines and then compute their ratios.
Concepts Tested
Formulas Used
1/λ = R Z^2 (1/n₁^2 - 1/n₂^2)
E_n = -13.6 Z^2/n^2
📚 NCERT Sections This Tests
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
12.6 — (A) Using The Bohr’S Model Calculate The Speed Of The Electron In A
Physics Class 12 · Chapter 12
12.6 (a) Using the Bohr’s model calculate the speed of the electron in a hydrogen atom in the n = 1, 2, and 3 levels. (b) Calculate the orbital period in each of these levels.
📋 Question Details
- Chapter
- Atoms
- Topic
- Bohr model, Hydrogen-like atoms
- Year
- 2012
- Shift
- 12 May Online
- Q Number
- Q27
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 12: Atoms
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