Molecule vs. Compound — Definition & Comparison

Molecule vs. Compound:

Before we dive into classifying what a molecule is and what a compound is, let’s first go over what atoms are!

• Atoms are super small and are made up of electrons, neutrons, and protons
• Atoms are what make up the chemical elements!

Here's an example of an oxygen atom:

Molecules vs Compounds:

Molecules and compounds are both made up of multiple atoms chemically bonded together via ionic bonding, covalent bonding, and metallic bonding.

• Molecules: Made up of multiple atoms
• Compounds: Made up multiple atoms that are different

An important idea to note is: All compounds are molecules, but not all molecules are compounds

Molecule Examples:

Molecules are just at least two atoms bonded together, this includes atoms that are the same (such as two oxygen atoms) and atoms that are different (such as one sodium atom (Na) and one chlorine atom (Cl)).

Examples: $O_{3}$ , $H_{2}O$ , $H_{2}SO_{4}$ , $NaCl$ , $H_{2}$

Compound Examples:

Compounds are at least two different atoms bonded together. There needs to be a least two different atoms present in order for the molecule to be classified as a compound.

• Compounds are visible to humans! so if you can see it, then it is a compound (like table salt: NaCl)

Examples: $C_{12}H_{22}O$ , $H_{2}O$ , $NaCl$ , $NH_{3}$

Molecules vs Compounds

As you can see in the image above, the molecule is made up of two of the same oxygen atoms, thus it is a molecule. The compound is made up of three atoms total, with two different types of atoms making its structure (oxygen and hydrogen) thus it is a compound!

Now let's try a practice problem!

Molecule vs Compound: Examples and Practice

by Wayne Breslyn

In this video, Dr. B explains the difference between molecules and compounds while providing examples.

All compounds are a type of molecule, but not all molecules are compounds. Molecules are the smallest part of any compound or element.

Molecules and Compounds: What's the Difference?

Molecules and compounds are both chemical species. They are defined by the type of atoms present.