Write true or false for the statement: The term atomic size refers to the distance between the centre of the nucleus and the penultimate shell of an isolated atom.

Where would you locate the element with electronic configuration $2, 8$ in the Modern Periodic Table?

Three elements $B$,$Si$ and $Ge$ are

Three elements $A$, $B$, and $C$ have $3$, $4$, and $2$ electrons respectively in their outermost shell. Determine the group number to which they belong in the Modern Periodic Table and state their valencies.

Arrange the following elements in the order of their decreasing metallic character:
$Na, Si, Cl, Mg, Al$

The element $X$ has the following electron configuration $2, 8, 8, 2$. It means that it belongs to: