Q51.Radius of the first excited state of Helium ion is given as : a0 → radius of first stationary state of hydrogen atom. (1) r = 4a0 (2) r = 2a0 (3) r = a02 (4) r = a04
What This Question Tests
This question directly applies Bohr's formula for the radius of an orbit in a hydrogen-like atom to calculate the radius of the first excited state of a Helium ion.
Concepts Tested
Formulas Used
r_n = a₀(n²/Z)
📚 NCERT Sections This Tests
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?
12.5 — 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.
12.4 — The Ground State Energy Of Hydrogen Atom Is –13.6 Ev. What Are The
Physics Class 12 · Chapter 12
12.4 The ground state energy of hydrogen atom is –13.6 eV. What are the kinetic and potential energies of the electron in this state?
📋 Question Details
- Chapter
- Atomic Structure
- Topic
- Bohr's Model Radius
- Year
- 2025
- Shift
- 22 Jan Shift 1
- Q Number
- Q51
- Type
- MCQ
- NCERT Ref
- Class 11 Chemistry Ch 2: Atomic Structure
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