What is a Compound? Definition of a Compound
A chemical element contains only one type of atom. If a substance contains more than one type of atom, it is a compound. In simple terms they can be described as substances that have two or more Atoms bonded together. There are millions of different chemical compounds. Different types of compounds are often expressed as chemical formulas or equations - see Examples of Compounds.

Types of Compounds - Hydrogen Peroxide
The chemical formula for the compound we know as water is H₂O indicating that 2 atoms of Hydrogen combines with 1 atom of oxygen. However, if another oxygen atom is added a new compound called Hydrogen Peroxide is created - H₂O₂ which indicates that 2 atoms of Hydrogen combines with 2 atoms of oxygen thus creating the compound Hydrogen Peroxide.

A Binary Compound
A binary compound is formed from two types of elements - their states of matter result in the following types of compound :

• Metal + Metal = Metallic Compound

• Metal + Non-Metal = Ionic compound

• Non-Metal + Non-Metal = Covalent compound

Types of Compounds - Categories - Ionic, Molecular and Acids
Most types of compounds fall in to one of three categories called ionic compounds, molecular compounds, or acids.

Types of Compounds

Ionic Compounds

Types of Compounds - Ionic, Cations, Anions
An Ion is an atom, or group of atoms, that bears an electric charge. The types of compounds referred to 'Ionic compounds' consist of combinations of positively charged ions called CATIONS (which are usually metals - pronounce as 'cat-ion') and negatively charged ions called ANIONS (which are usually non-metals - pronounce as 'an-eye-on'). In general, a compound will have no charge.

• Positively charged ions are called cations because they migrate towards the cathode (negative pole) in solution - they tend to lose electrons and form cations

• Negatively charged ions are called anions because they migrate towards the positive pole (anode) and are therefore known as anions - non-metals tend to gain electrons and form anions

• The positive cations and the negative anions then attract each other to form ionic bonds.

• Ionic compounds conduct electricity when dissolved in water or when molten

Types of Ionic Compounds
Examples of different types of Ionic Compounds are:

• NaCl (Sodium Chloride)

• CaBr2 (Calcium Bromide)

Molecular Compounds

Types of Compounds - What is the difference between a compound and a molecule?
Molecular compound. What is the difference between a compound and a molecule?

• A molecule is formed when two or more atoms join together chemically

• A compound is a molecule that contains at least two different elements

• All compounds are molecules, but not all molecules are compounds

Types of Compounds - Molecular Compound
Molecular compounds consist of combinations of non-metals. A Binary molecular compound is composed of only two elements.  Examples: H2O (water).

• Molecular compounds are easy to identify, as they consist merely of two non-metal elements

• Molecular compounds are non-conductors of electricity

Examples of Molecular Compounds
Examples of different types of Molecular Compounds are:

• H₂O (Hydrogen and Oxygen elements - Water)

• CH₄ (Carbon and Hydrogen elements - Methane)

Note: Molecular hydrogen (H₂), molecular oxygen (O₂) and molecular nitrogen (N₂) are not compounds because each is composed of a single element.

Acids

Types of Compounds - Acids
Acids are hydrogen containing compounds. Acids are easy to recognize- they are composed of hydrogen and an anion (the hydrogen always comes first), and they have no charge.

Types of Compounds - Examples of Acids
Examples of different types of Acids are made up of hydrogen and anions, and they do not have charges:

• H₂SO₄ (Sulfuric acid)

• HNO₃ (Nitric acid)

Types of  Common Compound
Some of the most common types and their chemical formulas can be accessed via Examples of Common Compounds.