The Periodic Table of Scarcity and Abundance
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Oxygen

Element 8 · Nonmetal

Specimen

Atomic number
8
Atomic mass
15.999
State at room temperature
Gas
Melting point
-218.8 °C
Boiling point
-183 °C
Density
0.001429 g/cm³
Discovered
1774

Physical data from PubChem.1

Can I eat it?

In food and water
Your body needs it. Oxygen is the most common element in the human body. It is in water and in food molecules such as glucose. 2

See every element.

The atom

O
ShellElectrons
1 (K) 2
2 (L) outermost 6
Total8

Configuration [He] 2s² 2p⁴

2s ↑ ↓
2p ↑ ↓ ↑ ↑
A shell diagram: each ring is an electron shell and each dot is one electron. The nucleus holds 8 protons. The outermost shell is shown in red. Electrons do not travel on rings: they fill orbitals, regions where an electron is likely to be found. The boxes are those orbitals for the electrons outside the He core, with one arrow per electron.

Related elements

Group 16
S Sulfur Se Selenium Te Tellurium Po Polonium Lv Livermorium

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Sources

  1. 1

    National Center for Biotechnology Information (PubChem), 2026. Periodic Table of Elements .

    Atomic mass, electron configuration, melting and boiling points, density and discovery year for all 118 elements.

  2. 2

    OpenStax, Rice University, 2022. Anatomy and Physiology 2e, section 2.1: Elements and Atoms: The Building Blocks of Matter .

    • beginning with the most abundant: oxygen (O), carbon (C), hydrogen (H), and nitrogen (N)
    • When two hydrogen atoms each share their single electron with oxygen, covalent bonds are formed, resulting in a molecule of water