What are examples of elements versus compounds?

Elements are pure substances made of only one type of atom and cannot be broken down into simpler substances by chemical means. Examples include hydrogen (H₂), oxygen (O₂), iron (Fe), and gold (Au). Each element has unique properties, such as atomic number and melting point.

Compounds are substances formed when two or more elements chemically combine in fixed proportions. For example, water (H₂O) consists of hydrogen and oxygen, and carbon dioxide (CO₂) is made of carbon and oxygen. The elements in a compound lose their original properties and form new ones.

To make it easy to remember:

• Element = single type of atom (example: Iron).
• Compound = two or more elements chemically bonded (example: Water).

A key difference is that elements are the building blocks of all matter, while compounds are combinations of these blocks. Compounds can be broken down into elements by chemical reactions, but elements cannot be further divided chemically.