What is the maximum number of electrons that the third shell (M shell) of an atom can hold?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 18
The maximum number of electrons in a shell is given by \(2n^2\), where \(n\) is the shell number. For the M shell, \(n=3\), so it can hold \(2\times3^2=18\) electrons (K shell 2, L shell 8).