Question

The maximum number of electrons that can occupy the K shell is :

• A. 1
• B. 8
• C. 2
• D. 18

Answer 1

Answer:

C. 2

• Bohr-Bury Scheme: The distribution of electrons in different shells is governed by the Bohr-Bury scheme.
• Formula: The maximum number of electrons that can be accommodated in a given shell is determined by the formula 2n², where 'n' represents the shell number (principal quantum number).
• Shell Identification: Shells are designated as K, L, M, N, O, P, and Q, corresponding to n = 1, 2, 3, 4, 5, 6, and 7 respectively.
• K Shell Calculation: For the K shell, the value of n is 1. Substituting this into the formula gives 2(1)² = 2(1) = 2 electrons.
• Subshell Configuration: The K shell contains only one subshell, the 1s subshell. Since an 's' orbital can hold a maximum of 2 electrons, the capacity of the K shell is capped at 2.
• Summary of Shell Capacities:
  • K shell (n=1): 2(1)² = 2 electrons
  • L shell (n=2): 2(2)² = 8 electrons
  • M shell (n=3): 2(3)² = 18 electrons
  • N shell (n=4): 2(4)² = 32 electrons
• Octet Rule Note: While higher shells can hold more electrons based on the 2n² rule, the outermost shell of an atom can generally hold a maximum of 8 electrons (octet rule) for stability.