Oxygen

Oxygen (O) is chemical element 8, in period 2, group 16.

Atomic number
8
Symbol
O
Also known as
O, 氧, 氧元素

Overview

Oxygen (O) is chemical element 8, in period 2, group 16.

Oxygen participates in many oxidation reactions and supports ordinary combustion. It is used in steelmaking and is a constituent of many organic compounds. Molecular oxygen and ozone are different elemental forms with different structures and reactivity.

Identifiers

Atomic number
8
Symbol
O
Also known as
O, 氧, 氧元素

Properties

Period
2
Group
16
Category (PubChem)
Nonmetal

References

  1. PubChem Periodic Table: element dataNational Center for Biotechnology Information · PubChem

    Retrieved 2026-09-16. Supplies all 118 atomic numbers, symbols, English names and reference categories. Atomic masses and state predictions are not imported as molecular properties.

  2. Periodic Table of ElementsInternational Union of Pure and Applied Chemistry · IUPAC

    Reference for accepted element names, symbols and periodic placement. Group numbers are omitted for the separately displayed lanthanoid and actinoid series.

  3. IUPAC化学元素周期表（中文版）中国化学会 · Chinese Chemical Society · 2019

    Simplified-Chinese element names and periodic-table positions checked against the January 2019 source.

  4. 化學名詞—化學元素一覽表國家教育研究院化學名詞審譯委員會 · National Academy for Educational Research · 2017

    Official 2017 revised list redistributed by 臺南市立將軍國民中學. The attached 20170818化學元素表.doc was downloaded and all 118 number/symbol/name rows checked. Component glyph descriptions are represented by their Unicode characters; documented regional names are retained as search aliases.

  5. It's Elemental: OxygenThomas Jefferson National Accelerator Facility · Jefferson Lab, U.S. Department of Energy

    Element-use and material context checked in the source annotations supplied by the PubChem element page on 2026-09-16. No preparation instructions, current production quantities or medical advice are imported.

  6. Accessing the Chemical Elements Data from PubChemSunghwan Kim · IUPAC FAIR Chemistry Cookbook · 2024

    Documents the PubChem element-data service, its 118-row coverage and derivation of periods from atomic numbers.