Chapter 4, Problem 15A

Interpretation Introduction

Interpretation:

The oxyanion containing maximum oxygen atoms is to be chosen

Concept introduction:

Oxyanion is a class of polyatomic ions. Polyatomic ion involves more than one atom which carries a net charge and exists as a single unit. Oxyanion is an anion of oxygen and another non-metal. For example: sulphate ion $(S{O}_4{}^{2-})$ , Phosphate ion $(P{O}_4{}^{3-})$

Answer to Problem 15A

Perchlorate ion

Explanation of Solution

The rules which are used to name series of oxyanions are:

• The standard anion ends with ‘ate’.
• For the anion carrying one more oxygen, prefix ‘per’ is used.
• The anion carrying one less oxygen atom ends with ‘ite’.
• The anion carrying two less oxygen ends with ‘ite’ and prefix ‘hypo’ is also used.

Chlorate ion is the standard ion for naming oxyanions of chlorine.

Formula	Name
$Cl{O}_4{}^{-}$	Perchlorate ion
$Cl{O}_3{}^{-}$	Chlorate ion
$Cl{O}_2{}^{-}$	Chlorite ion
$Cl{O}^{-}$	Hypochlorite ion

Conclusion

Thus, perchlorate ion contains maximum number of oxygen atoms.