Chemistry Atomic Structure ETEA 2019
PMDC Verified Question 77 of 95
Quantum number which describes the orientation of orbitals in three dimensional space is:
A
Spin quantum number
B
Azimuthal quantum number
C
Principal quantum number
D
Magnetic quantum number
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: Magnetic quantum number
Concept: Each of the four quantum numbers defines a unique aspect of an electron's state in an atom.

Formula: None required.

Solution:
  • Principal (\(n\)): Distance from nucleus / Energy level.
  • Azimuthal (\(l\)): Shape of the orbital (e.g., sphere, dumbbell).
  • Magnetic (\(m\)): Spatial orientation of the orbital along the x, y, and z axes in a magnetic field.
  • Spin (\(s\)): Intrinsic angular momentum (spin) of the electron.


Why other options are incorrect: Only the magnetic quantum number corresponds to 3D spatial orientation.

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