Oxygen

chemistry · life · elements

The air we breathe. Oxygen makes up about 21% of the air around us. Every time you take a breath, you're pulling oxygen into your lungs so your body can use it for energy.

Most abundant on Earth. Oxygen is the most common element in Earth's crust, making up almost half of it. It hides inside water, rocks, sand, and soil all around you.

Super reactive element. Oxygen loves to combine with other elements, which is why we see it in water (H2O), carbon dioxide (CO2), and even rust on old bikes. It's one of the most eager elements to bond with others.

Helps things burn. Oxygen is a powerful oxidizing agent, which means it helps fires burn and helps your body break down food for energy. Without oxygen, many of the chemical reactions we depend on couldn't happen.

Third most abundant in space. After hydrogen and helium, oxygen is the third-most abundant element in the entire universe, created inside giant stars.