Trivalent Ions – Cations and Anions

 The theories proposed till now explains the physical and chemical properties of different elements found.The studies by different scientists have contributed to the expansion of the periodic table and described various other participants of atomic chemistry. Such as molecules, isotopes, ions, radicals, compounds, etc.

Atoms are  known as tiny particles of elements that take place in a chemical reaction. Molecules are a group of two or more atoms that form the smallest unit.

The atoms of different elements have their own nature some are stable and some attain stability by sharing their valence electron with other atoms. While molecules are bonded together with chemical bonds. The diagram of the molecule was published by John Dalton. Some examples of molecules are nitrogen gas, water, table salt, etc.

What are Ions?

Ions are atoms or groups of atoms that are electrically charged and carry positive or negative charges. The formation of ions takes place due to the losing or sharing of electrons.

Anions and Cations

An anion is an ion carrying a negative charge. Anions are formed by the gaining of electrons from other atoms due to which they develop a negative charge. Simply, it means the atom has a higher number of electrons than the protons. There are four types of anions. They are listed below,

• Monovalent Anions
• Divalent Anions
• Trivalent Anions
• Tetravalent Anions

A cation is an ion carrying a positive charge. Cations are formed by losing electrons due to which they develop a positive charge. It means the atom has a higher number of protons than that of electrons. There are four types of cations. They are listed below,

• Monovalent Cations
• Divalent Cations
• Trivalent Cations
• Tetravalent Cations

What are Trivalent Cations (+3)?

Trivalent Cations are the positively charged ions having their valency (3+). It means divalent ions are formed by losing three valence electrons and attaining a positive charge. 

The cation is denoted by superscript 3+ on the symbol of atom or group of atoms. Some of the examples of trivalent cations are Aluminium(Al³⁺), Chromium(Cr³⁺), etc.

List of Trivalent Cations

Name	Formula
Aluminium	Al3+
Chromium	Cr3+
Iron [III]	Fe3+
Gold	Au3+

Some metals, such as copper, mercury, and iron, produce two kinds of ions with different charges or valencies. As an example:

1. Copper metal (Cu) produces two ions Cu⁺ and Cu²⁺: The Cu+ ion with one unit positive charge is referred to as the copper (I) ion, where (I) indicates that the ion has a valency of 1+. The cuprous ion is another name for the copper (I) ion Cu⁺. The second copper ion, Cu²⁺, contains two units of positive charge and is referred to as copper(II) ion, where (II) indicates that the ion has a valency of 2+. The cupric ion is another name for the copper (II) ion Cu²⁺.
2. Mercury metal (Hg) also produces two ions, Hg⁺ and Hg²⁺: Mercury is the name given to the Hg⁺ ion. It is a Mercury (I) ion or mercurous ion with a valency of 1+. Hg⁺² ion, on the other hand, is also known as mercury (II) ion or mercuric ion and has a valency of 2+.
3. Iron metal (Fe) produces two ions, Fe²⁺ and Fe³⁺: The Fe²⁺ ion is also known as iron (II) ion or ferrous ion and has a 2+ valency. The Fe³⁺ ion is also known as iron (III) ion or ferric ion and has a 3+ valency.

What are Trivalent Anions (3-)?

Trivalent Anions are the negatively charged ions having their valency (3-). It means trivalent anions are formed by gaining three valence electrons and attaining a negative charge. 

The anion is denoted by superscript 3- on the symbol of atom or group of atoms. Some of the examples of trivalent anions are Nitride(N^3- ), Phosphate(PO₄^3- ) etc.

List of Trivalent Anions

Name	Formula
Nitride	N3-
Phosphate	PO3-
Ferricyanide	Fe(CN)63-
Phosphide	P3-

Sample Questions

Question 1: What is the charge carried by a cation?

Answer:

An anion is electropositive and carries a positive charge because of the loss of electrons.

Question 2: What are the types of anions?

Answer:

Anions are categorized into four types based on their valency which are listed below:

• Monovalent Anions
• Divalent Anions
• Trivalent Anions
• Tetravalent Anions

Question 3: Barium is kept in the group of divalent cations, why?

Answer:

Barium is a divalent cation because it has valency two and carries a positive charge by gaining electrons from others.

Question 4: Enlist the types of ions based on their valency.

Answer:

The types of ions based on their valency are listed below:

• Monovalent ions
• Divalent ions
• Trivalent ions
• Tetravalent ions

Question 5: Can atoms of the same element for two or more types of ions?

Answer:

Yes, the elements having atoms with variable valency can form more types of ions. For example copper, iron, etc.

Question 6: Phosphate is kept in the group of trivalent anions, why?

Answer:

Phosphate is a trivalent anion because it has valency three  and carries a negative charge by gaining electrons from others.