Chapter U1, Problem 7RE

Interpretation Introduction

Interpretation:

The cations and anions should be described.

Concept introduction:

An atom or group of atoms that possess charge is known as ion.

Answer to Problem 7RE

An atom or group of atoms that possess charge is known as ion. When the charge is positive then the ion is said to be cation whereas negative charge bearing atom is anion.

Explanation of Solution

An atom or group of atoms that possess charge is known as ion. The ions possess charge because they have fewer or greater number of electrons compared to the number of protons.

The loss of electron from an atom results in the formation of ion known as cation and it possesses positive charge, whereas the gain of electron by an atom results in the formation of anion and it possess negative charge.

For example:

$\text{Na}$ forms cation by losing an electron in order to complete its octet and obtain a positive charge ${\text{Na}}^{\text{+}}$.

$\text{Cl}$ forms anion by gaining an electron in order to complete its octet and obtain a negative charge ${\text{Cl}}^{-}$.