Chapter U2, Problem 19STP

Interpretation Introduction

Interpretation:

The group of elements having highest electronegativity values needs to be identified.

Concept introduction:

The atom’s tendency to attract the shared electrons or pair of bonds is recognized as electronegativity of that atom.

Answer to Problem 19STP

The correct answer is (B).

Explanation of Solution

Electronegativity usually increases on moving from left to right across the period. It usually decreases decrease from top to bottom in a group because of larger atomic size. This is because of a rise in nuclear charge. Alkali metals contain the lowest electronegativity values, whereas the highest electronegativity values are present in halogens.

Electronegativity is dependent on the attraction between the bonding electrons and nucleus within the outer shell. This reactivity is because of high effective nuclear charge and high electronegativity. The halogen gains electron by reacting with other elements. The oxygen atoms contain a smaller atomic radius, towards the nucleus the bonding electrons are nearer and thus apply a greater pull.

So, the most electronegative atoms are Fluorine, Oxygen and Nitrogen. And in the given set of elements the most electronegative group of elements are O(oxygen), Cl(chlorine) and F(fluorine). Chlorine and fluorine both belongs to the halogen family.

So, the correct answer is (B).