Question

Which of the following elements has the least non – metallic character?
(A) Fluorine
(B) Chlorine
(C) Bromine
(D) Iodine

Answer 1

Hint:
 As we know that according to trends of the periodic table, the non – metallic character increases from left to right and decreases from top to bottom in the periodic table whereas metallic character increases going down a group.

Complete step by step answer:
The metallic character of a metal is the level of the reactivity of a metal. As you know that metals lose electrons in chemical reactions, as this is clearly seen from their low ionization energies. Metal atoms are found to have low attraction for electrons in any compound.
According to the periodic trends, the most reactive metals are in the lower left portion of the periodic table. The most reactive metal is caesium. It is not found in nature as a free element. It reacts with water explosively and ignites spontaneously in the air. As we know according to the periodic table, Francium is found below caesium in the alkali metal group but due to its rare availability its properties are never observed.
As non- metals tend to gain electrons in the chemical reactions and in contrast to metals, they have high attraction for electrons within a compound. The most reactive non – metals are in the upper right portion of the periodic table. Among halogens, fluorine is the most reactive non – metal. It was not found as a free element in nature.
The order of non – metallic character among halogens is:
$F > Cl > Br > I$
As you see fluorine is the most reactive non – metal whereas iodine is the least reactive one.
Hence, option D is correct.

Note: There is no such clear division between metallic and non – metallic character. It is in a way that as we move across the periodic table, tendency to accept electrons increases which means non-metallic character increases.