Question

If the K and L shells of an atom are full, then what will be the total number of electrons in the atom?

• A. 12
• B. 8
• C. 10
• D. 16

Answer 1

Answer: (C)

10

The maximum number of electrons in first orbit or K-shell will be $2\times 1^2=2$ and second orbit or L-shell will be $2\times 2^2=8$. Hence, if K and L shell is full, the total number of electrons in the atom will be 2+8 = 10.