What NEET Asks
- Direct questions on general electronic configuration.
- Identifying specific configurations for N, P, As, Sb, Bi.
- Questions on stability related to half-filled orbitals.
Key Points
- Group 15 elements are also known as the Nitrogen Family or Pnictogens.
- Their general valence shell electronic configuration is
ns²np³. - This configuration indicates 5 valence electrons in total.
- The
np³configuration signifies a half-filled p-orbital, contributing to enhanced stability. - Nitrogen (N, Z=7):
[He]2s²2p³ - Phosphorus (P, Z=15):
[Ne]3s²3p³ - Arsenic (As, Z=33):
[Ar]3d¹⁰4s²4p³ - Antimony (Sb, Z=51):
[Kr]4d¹⁰5s²5p³ - Bismuth (Bi, Z=83):
[Xe]4f¹⁴5d¹⁰6s²6p³
Must-Know Formula / Reaction
- General Electronic Configuration:
ns²np³n: Principal quantum number of the outermost shell.s: s-subshell, holds 2 electrons.p: p-subshell, holds 3 electrons (half-filled).
Common Mistakes
- Students often forget to include the filled d-orbitals for heavier elements (As, Sb, Bi) in the complete electronic configuration.
- Don't confuse the general valence shell configuration (
ns²np³) with the complete configuration. - Incorrectly applying Hund's rule or Pauli's exclusion principle when determining unpaired electrons.
Rapid Revision
Group 15 elements have a characteristic ns²np³ valence shell configuration with 5 valence electrons. This half-filled p-orbital arrangement provides extra stability. Remember the specific configurations for N, P, As, Sb, Bi, especially including d and f orbitals for heavier members.