Chapter 7, Problem 57A

(a)

Interpretation Introduction

Interpretation: To arrange the atoms according to the increasing size.

Concept introduction:

An ion is formed by losing or gaining one or more electrons which helps them to attain a stable noble gas configuration.

Answer to Problem 57A

oxygen atom < oxide ion < sulfur atom < sulfide ion

Explanation of Solution

Atomic size increases down the group. This is because when moving from top to bottom in the group, both the number of shells and nuclear charge increase. The effect of more shells, however, outweighs the effect of a higher nuclear charge which results in an increase in atomic radius.

The element oxygen and sulfur belong to group 16, where oxygen is placed above sulfur, therefore, the size of the sulfur atom is more than oxygen atom.

The negatively charged ion has a larger size as compared to its neutral atom, as a negative ion is created by adding extra electrons, which in turn increase the size of the ion.

Hence, the increasing size is,

oxygen atom < oxide ion < sulfur atom < sulfide ion

(b)

Interpretation Introduction

Interpretation: To arrange the atoms according to the increasing size.

Concept introduction:

An ion is formed by losing or gaining one or more electrons which helps them to attain a stable noble gas configuration.

Answer to Problem 57A

sodium ion < sodium atom < potassium ion < Potassium atom

Explanation of Solution

The element potassium and sodium belong to the group 1 of the periodic table, where sodium is placed above potassium, therefore, the size of the potassium atom is more than the sodium atom.

The positively charged ion has a smaller size as compared to its neutral atom, as a positive ion is created by removing the electrons from the valence shell, which in turn decreases the size of the ion.

Hence, the increasing size is,

sodium ion < sodium atom < potassium ion < Potassium atom