When we start learning about Grade 9 Chemistry, one important topic is the difference between molecules and compounds. Although they may sound alike, it’s essential to understand how they differ.

Molecules are created when two or more atoms stick together. They can be made of the same kind of atom or different kinds. Here are a couple of examples:

• Oxygen molecule (O₂): This is made up of two oxygen atoms joined together.
• Hydrogen molecule (H₂): This one has two hydrogen atoms that are linked together.

Compounds, on the other hand, are a special kind of molecule. They form when two or more different types of atoms bond. This means that while all compounds are molecules, not all molecules are compounds! For instance:

• Water (H₂O): This is a compound that has two hydrogen atoms and one oxygen atom.
• Table salt (NaCl): This is a compound made from sodium and chlorine atoms.

Here’s an easy way to remember the difference:

• Molecule: A general term for groups of atoms bonded together, which can be the same or different types.
• Compound: A specific type of molecule made from two or more different types of atoms.

In short, both molecules and compounds involve atoms bonding together. But remember, molecules can be made of the same or different atoms, while compounds must always be made of different atoms. Keeping this in mind will really help you as we explore more in chemistry!