Question

The atomic number of an element $M$ is $26$. How many electrons are present in the $M$-shell of the element in its state

• A. $14$
• B. $13$
• C. $11$
• D. $15$

Answer 1

Answer: (B)

$13$

Answer 2

It is an example of Fe atom $Fe \to K \to 1 s^{2}$ $L \to 2s^{2}\,2p^{6}$ $M \to 3s^{2}\,3p^{6}\,3d^{6}$ $N \to 4s^{2}$ $Fe^{3+} \to K \to 1s^{2}$ $L \to 2s^{2}\,2p^{6}$ $M \to 3s^{2}\,3p^{6}\,3d^{5}$ Total number of electrons in M shell is $13$