Which one of the following elements exhibits the maximum number of valence electrons?

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.

The following table shows elements represented by the letters $A, B, C, D, E, F, G$ and $H$.

Group	$1$	$2$	$13$	$14$	$15$	$16$	$17$	$18$
Element	$A$	$B$	$C$	$D$	$E$	$F$	$G$	$H$

$(i)$ Which of the elements has the atomic size:
$(a)$ biggest and $(b)$ smallest?
$(ii)$ Which element has valency:
$(a)$ $3$ and $(b)$ zero?

Which of the following sets of elements is written in the order of their increasing metallic character?

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

The position of three elements $A$,$B$ and $C$ in the Periodic Table are shown below:

Group $16$	Group $17$
-	-
-	$A$
-	-
$B$	$C$

$(a)$ Will $C$ be larger or smaller in size than $B$?
$(b)$ Which type of ion,cation or anion,will be formed by element $A$?