Question

In the pinwheel galaxy, atomic number of all elements are the same as that on earth and paulis principle is obeyed. However the shell closest to the nucleus is saturated with electrons before the next shell starts to fill and the process continues this way, also each orbital can accommodate only one electron having $+\frac{1}{2}$ spin. If noble gases are defined as the elements with completely filled outermost shell, which elements would be the nobel gas in their periodic table ?

• A. $Ar$
• B. $Si$
• C. $F$
• D. $Ne$

Answer 1

Answer: (B)

$Si$

Maximum number of electrons in an orbit = $n^2$ (instead of $2n^2$, due to orbital capacity getting halved).

$1s^1$
$2s^1,2p^3$
$3s^1,3p^3,3d^5$

$Z=14=Si$