ABCDEFGHIJKLMNOPQRSTUVWXYZ
o+ (1)
 Atomic data: Oxygen
 
o+1 (1)
 Data2: Oxygen
 
o+2 (1)
 Data2: Oxygen
 
o0 (1)
 Data2: Oxygen
 
o10 (4)
 Data1: Caesium
 Data1: Lithium
 Data1: Rubidium
 Production: Lithium
 
o16 (1)
 Data1: Samarium
 
o2 (75)
 Allotrope: Oxygen
 Country: Outer space
 Data1: Oxygen
 Data2: Oxygen
 Glossary: Allotrope
 Glossary: Endothermic
 Glossary: Molecule
 Glossary: Temperature
 Production: Aluminium
 Production: Hydrogen
 Production: Iron
 Production: Mercury
 Reactions: Actinium
 Reactions: Aluminium
 Reactions: Antimony
 Reactions: Arsenic
 Reactions: Barium
 Reactions: Beryllium
 Reactions: Bismuth
 Reactions: Boron
 Reactions: Bromine
 Reactions: Cadmium
 Reactions: Caesium
 Reactions: Calcium
 Reactions: Carbon
 Reactions: Cobalt
 Reactions: Copper
 Reactions: Dysprosium
 Reactions: Erbium
 Reactions: Fluorine
 Reactions: Gadolinium
 Reactions: Germanium
 Reactions: Hafnium
 Reactions: Holmium
 Reactions: Iridium
 Reactions: Iron
 Reactions: Lanthanum
 Reactions: Lead
 Reactions: Lithium
 Reactions: Magnesium
 Reactions: Manganese
 Reactions: Mercury
 Reactions: Molybdenum
 Reactions: Nickel
 Reactions: Osmium
 Reactions: Oxygen
 Reactions: Palladium
 Reactions: Phosphorus
 Reactions: Polonium
 Reactions: Potassium
 Reactions: Praseodymium
 Reactions: Radium
 Reactions: Rhenium
 Reactions: Rhodium
 Reactions: Rubidium
 Reactions: Ruthenium
 Reactions: Samarium
 Reactions: Scandium
 Reactions: Selenium
 Reactions: Silicon
 Reactions: Sodium
 Reactions: Strontium
 Reactions: Sulfur
 Reactions: Technetium
 Reactions: Tellurium
 Reactions: Terbium
 Reactions: Thallium
 Reactions: Thulium
 Reactions: Tin
 Reactions: Titanium
 Reactions: Tungsten
 Reactions: Vanadium
 Reactions: Yttrium
 Reactions: Zinc
 Reactions: Zirconium
 
o22eu2o3 (1)
 Reactions: Europium
 
o22lu2o3 (1)
 Reactions: Lutetium
 
o22nd2o3 (1)
 Reactions: Neodymium
 
o22yb2o3 (1)
 Reactions: Ytterbium
 
o2ceo2 (1)
 Reactions: Cerium
 
o3 (8)
 Allotrope: Oxygen
 Compounds: Oxygen
 Data1: Oxygen
 Glossary: Allotrope
 Reactions: Bromine
 Reactions: Fluorine
 Reactions: Iodine
 Reactions: Oxygen
 
o4 (3)
 Allotrope: Oxygen
 Data1: Zinc
 Glossary: Allotrope
 
o6 (9)
 Data1: Dysprosium
 Data1: Erbium
 Data1: Niobium
 Data1: Rhenium
 Data1: Scandium
 Data1: Terbium
 Data1: Thulium
 Production: Niobium
 Production: Terbium
 
oacute (2)
 Country: Colombia
 On This Day... 2 February
 
oak (5)
 Biography: Philip Hauge Abelson
 Data1: Einsteinium
 Data1: Plutonium
 Data1: Promethium
 Production: Einsteinium
 
obeys (3)
 Glossary: Ideal Gas
 On This Day... 14 October
 Production: Holmium
 
object (8)
 Biography: Julius Caesar Scaliger
 Biography: William Hyde Wollaston
 Data1: Antimony
 Data1: Carbon
 Equation: Density
 Glossary: Absorption Spectrum
 Glossary: Heat Capacity
 Glossary: Temperature
 
objected (2)
 Biography: Julius Caesar Scaliger
 Data1: Seaborgium
 
objections (2)
 Biography: Julius Caesar Scaliger
 Glossary: X-Rays
 
objective (1)
 Compounds: Germanium
 
objects (8)
 Compounds: Fluorine
 Compounds: Oxygen
 Data1: Magnesium
 Data1: Radium
 Data1: Zinc
 Glossary: Absorption Spectrum
 Isotope: Magnesium
 Isotope: Ytterbium
 
obliged (1)
 Biography: Julius Caesar Scaliger
 
obo (4)
 Country: China
 Country: Russia
 Country: Ukraine
 Data1: Europium
 
obr (1)
 Reactions: Bromine
 
obscure (1)
 Production: Lanthanum
 
observable (5)
 Country: Outer space
 Data1: Roentgenium
 Data1: Ununbium
 Data1: Ununpentium
 Data1: Ununtrium
 
observation (8)
 Biography: John William Strutt Rayleigh
 Biography: Julius Caesar Scaliger
 Biography: Pierre Jules César Janssen
 Data1: Ununoctium
 On This Day... 14 March
 On This Day... 24 February
 On This Day... 24 January
 On This Day... 29 August
 
observations (6)
 Biography: Julius Caesar Scaliger
 Biography: Karl Wilhelm Scheele
 Biography: Pierre Jules César Janssen
 Data1: Iodine
 Data1: Technetium
 Glossary: Double Electron Capture
 
observatoire (1)
 Biography: Pierre Jules César Janssen
 
observatory (3)
 Biography: Pierre Jules César Janssen
 Biography: Sir William Crookes
 On This Day... 11 January
 
observe (4)
 Data1: Lithium
 Data1: Terbium
 Glossary: Temperature
 Glossary: Vickers Hardness
 
observed (24)
 Allotrope: Carbon
 Biography: Hans Christian Oersted
 Biography: Jöns Jacob Berzelius
 Biography: Pierre Jules César Janssen
 Biography: William Hyde Wollaston
 Compounds: Neon
 Compounds: Plutonium
 Country: Australia
 Data1: Argon
 Data1: Californium
 Data1: Gadolinium
 Data1: Helium
 Data1: Platinum
 Data1: Roentgenium
 Document: The Alkali (Group 1) Metals
 Glossary: Double Beta Decay
 Glossary: Enthalpy Change of Fusion (Heat of Fusion)
 Glossary: Magnetic Ordering
 Glossary: X-Rays
 Isotope: Californium
 Isotope: Magnesium
 Isotope: Tungsten
 On This Day... 18 February
 Production: Nitrogen
 
observer (2)
 Biography: Julius Caesar Scaliger
 Glossary: Emission Spectrum
 
observing (3)
 Biography: Pierre Jules César Janssen
 Data1: Terbium
 Data1: Thulium
 
obsessed (1)
 Biography: Dmitriy Ivanovich Mendeleyev
 
obsolete (3)
 Data1: Lanthanum
 Data1: Phosphorus
 Glossary: Rare Earth Elements
 
obstacles (1)
 Biography: Jöns Jacob Berzelius
 
obtain (18)
 Biography: Louis Jacques Thenard
 Biography: Philip Hauge Abelson
 Compounds: Cadmium
 Data1: Dysprosium
 Data1: Erbium
 Data1: Gold
 Data1: Lutetium
 Data1: Thulium
 Data1: Tungsten
 Data1: Uranium
 Production: Astatine
 Production: Barium
 Production: Magnesium
 Production: Plutonium
 Production: Potassium
 Production: Selenium
 Reactions: Bromine
 Reactions: Fluorine
 
obtained (64)
 Allotrope: Phosphorus
 Biography: Bernard Courtois
 Biography: Ferdinand Reich
 Biography: John William Strutt Rayleigh
 Biography: Joseph Louis Gay-Lussac
 Biography: Julius Caesar Scaliger
 Biography: Lise Meitner
 Biography: Morris Travers
 Biography: Peter Armbruster
 Biography: Philip Hauge Abelson
 Compounds: Erbium
 Country: United Kingdom
 Country: United States of America
 Data1: Actinium
 Data1: Aluminium
 Data1: Boron
 Data1: Cadmium
 Data1: Calcium
 Data1: Cerium
 Data1: Copper
 Data1: Europium
 Data1: Fluorine
 Data1: Gadolinium
 Data1: Gallium
 Data1: Germanium
 Data1: Hafnium
 Data1: Hydrogen
 Data1: Krypton
 Data1: Lithium
 Data1: Magnesium
 Data1: Neodymium
 Data1: Nickel
 Data1: Osmium
 Data1: Oxygen
 Data1: Palladium
 Data1: Praseodymium
 Data1: Rhodium
 Data1: Rubidium
 Data1: Ruthenium
 Data1: Selenium
 Data1: Sodium
 Data1: Tellurium
 Data1: Thulium
 Data1: Titanium
 Data1: Xenon
 Glossary: Atomic Radius
 On This Day... 17 September
 On This Day... 22 March
 On This Day... 23 March
 On This Day... 7 July
 Production: Aluminium
 Production: Dysprosium
 Production: Fluorine
 Production: Germanium
 Production: Lutetium
 Production: Magnesium
 Production: Rhenium
 Production: Rhodium
 Production: Samarium
 Production: Selenium
 Production: Silver
 Production: Thallium
 Production: Xenon
 Production: Zinc
 
obtaining (6)
 Biography: Karl Wilhelm Scheele
 Biography: Lise Meitner
 Biography: Walter Noddack
 Data1: Barium
 Data1: Boron
 Production: Magnesium
 
obvious (1)
 Biography: Irene Joliot-Curie
 
oc (1)
 Allotrope: Carbon
 
occasion (1)
 Biography: Irene Joliot-Curie
 
occasionally (4)
 Compounds: Potassium
 Glossary: X-Rays
 Production: Silicon
 Production: Technetium
 
occupational (2)
 Data1: Radium
 Data1: Uranium
 
occupied (1)
 Biography: Irene Joliot-Curie
 
occupies (1)
 Equation: Avogadro's law
 
occur (46)
 Allotrope: Sulfur
 Biography: Emilio Gino Segre
 Compounds: Fluorine
 Compounds: Silver
 Compounds: Titanium
 Data1: Astatine
 Data1: Bohrium
 Data1: Californium
 Data1: Chromium
 Data1: Copper
 Data1: Lawrencium
 Data1: Lithium
 Data1: Manganese
 Data1: Promethium
 Data1: Protactinium
 Data1: Rubidium
 Data1: Vanadium
 Document: The Actinoid Series
 Document: The Noble Gases (Group 18)
 Document: The Transition Metals (Groups 3 to 12)
 Glossary: Actinides
 Glossary: Actinoids
 Glossary: Double Electron Capture
 Glossary: Electron Capture
 Glossary: Endothermic
 Glossary: Lanthanides (old name)
 Glossary: Lanthanoids
 Glossary: Magnetic Ordering
 Glossary: Spontaneous Fission
 Isotope: Californium
 Isotope: Hydrogen
 Production: Cadmium
 Production: Carbon
 Production: Holmium
 Production: Lead
 Production: Lithium
 Production: Mercury
 Production: Niobium
 Production: Rhodium
 Production: Silicon
 Production: Technetium
 Production: Terbium
 Production: Thallium
 Production: Thorium
 Production: Uranium
 Production: Vanadium
 
occurence (2)
 Production: Astatine
 Production: Plutonium
 
occuring (1)
 Glossary: Allobar
 
occurred (8)
 Biography: William Hyde Wollaston
 Data1: Fermium
 Data1: Gold
 Data1: Lead
 Data1: Phosphorus
 Data1: Radon
 Data1: Silicon
 Production: Fermium
 
occurrence (120)
 Biography: Franz-Joseph Muller Freiherr von Reichenstein
 Data1: Germanium
 Production: Actinium
 Production: Aluminium
 Production: Americium
 Production: Antimony
 Production: Argon
 Production: Arsenic
 Production: Astatine
 Production: Barium
 Production: Berkelium
 Production: Beryllium
 Production: Bismuth
 Production: Bohrium
 Production: Boron
 Production: Bromine
 Production: Cadmium
 Production: Caesium
 Production: Calcium
 Production: Californium
 Production: Carbon
 Production: Cerium
 Production: Chlorine
 Production: Chromium
 Production: Cobalt
 Production: Copper
 Production: Curium
 Production: Darmstadtium
 Production: Dubnium
 Production: Dysprosium
 Production: Einsteinium
 Production: Erbium
 Production: Europium
 Production: Fermium
 Production: Fluorine
 Production: Francium
 Production: Gadolinium
 Production: Gallium
 Production: Germanium
 Production: Gold
 Production: Hafnium
 Production: Hassium
 Production: Helium
 Production: Holmium
 Production: Hydrogen
 Production: Indium
 Production: Iodine
 Production: Iridium
 Production: Iron
 Production: Krypton
 Production: Lanthanum
 Production: Lawrencium
 Production: Lead
 Production: Lithium
 Production: Lutetium
 Production: Magnesium
 Production: Manganese
 Production: Meitnerium
 Production: Mendelevium
 Production: Mercury
 Production: Molybdenum
 Production: Neodymium
 Production: Neon
 Production: Neptunium
 Production: Nickel
 Production: Niobium
 Production: Nitrogen
 Production: Nobelium
 Production: Osmium
 Production: Oxygen
 Production: Palladium
 Production: Phosphorus
 Production: Platinum
 Production: Plutonium
 Production: Polonium
 Production: Potassium
 Production: Praseodymium
 Production: Promethium
 Production: Protactinium
 Production: Radium
 Production: Radon
 Production: Rhenium
 Production: Rhodium
 Production: Roentgenium
 Production: Rubidium
 Production: Ruthenium
 Production: Rutherfordium
 Production: Samarium
 Production: Scandium
 Production: Seaborgium
 Production: Selenium
 Production: Silicon
 Production: Silver
 Production: Sodium
 Production: Strontium
 Production: Sulfur
 Production: Tantalum
 Production: Technetium
 Production: Tellurium
 Production: Terbium
 Production: Thallium
 Production: Thorium
 Production: Thulium
 Production: Tin
 Production: Titanium
 Production: Tungsten
 Production: Ununbium
 Production: Ununhexium
 Production: Ununoctium
 Production: Ununpentium
 Production: Ununquadium
 Production: Ununseptium
 Production: Ununtrium
 Production: Uranium
 Production: Vanadium
 Production: Xenon
 Production: Ytterbium
 Production: Yttrium
 Production: Zinc
 Production: Zirconium
 
occurring (32)
 Allotrope: Phosphorus
 Allotrope: Tin
 Biography: Morris Travers
 Compounds: Radium
 Compounds: Zirconium
 Data1: Astatine
 Data1: Caesium
 Data1: Chlorine
 Data1: Francium
 Data1: Iridium
 Data1: Osmium
 Data1: Platinum
 Data1: Rhenium
 Glossary: Double Beta Decay
 Glossary: Double Electron Capture
 Glossary: Enzyme
 Glossary: Noble Gasses (inert gasses)
 Glossary: Rare Earth Elements
 Isotope: Carbon
 Isotope: Manganese
 Isotope: Tungsten
 On This Day... 6 November
 Production: Aluminium
 Production: Astatine
 Production: Iridium
 Production: Osmium
 Production: Platinum
 Production: Promethium
 Production: Scandium
 Production: Sulfur
 Production: Uranium
 Production: Xenon
 
occurs (71)
 Allotrope: Carbon
 Biography: Ida Eva Tacke Noddack
 Biography: Robert Wilhelm Bunsen
 Compounds: Carbon
 Compounds: Copper
 Country: Democratic Republic of Congo
 Country: Oceans / Seas
 Country: Outer space
 Country: South Africa
 Data1: Aluminium
 Data1: Bromine
 Data1: Cadmium
 Data1: Calcium
 Data1: Cobalt
 Data1: Copper
 Data1: Dysprosium
 Data1: Holmium
 Data1: Iodine
 Data1: Lead
 Data1: Neodymium
 Data1: Niobium
 Data1: Osmium
 Data1: Palladium
 Data1: Polonium
 Data1: Protactinium
 Data1: Rhodium
 Data1: Rubidium
 Data1: Scandium
 Data1: Tantalum
 Data1: Technetium
 Data1: Titanium
 Data1: Tungsten
 Data1: Uranium
 Data1: Yttrium
 Glossary: Double Beta Decay
 Glossary: Double Electron Capture
 Glossary: Emission Spectrum
 Glossary: Enthalpy Change of Fusion (Heat of Fusion)
 Glossary: Isometric Transition
 Glossary: Magnetic Ordering
 Isotope: Carbon
 On This Day... 19 March
 Production: Arsenic
 Production: Bromine
 Production: Caesium
 Production: Calcium
 Production: Gadolinium
 Production: Hydrogen
 Production: Iodine
 Production: Lanthanum
 Production: Lead
 Production: Manganese
 Production: Neodymium
 Production: Nitrogen
 Production: Osmium
 Production: Platinum
 Production: Protactinium
 Production: Rhodium
 Production: Rubidium
 Production: Ruthenium
 Production: Samarium
 Production: Selenium
 Production: Silicon
 Production: Strontium
 Production: Sulfur
 Production: Tantalum
 Production: Thallium
 Production: Thorium
 Production: Titanium
 Production: Yttrium
 Reactions: Carbon
 
ocean (8)
 Compounds: Chlorine
 Compounds: Sodium
 Country: Oceans / Seas
 Data1: Carbon
 Data1: Manganese
 Data1: Zirconium
 Production: Manganese
 Production: Thallium
 
oceans (7)
 Country: Oceans / Seas
 Data1: Chlorine
 Production: Chlorine
 Production: Gold
 Production: Molybdenum
 Production: Potassium
 Production: Uranium
 
ochre (1)
 Data1: Bismuth
 
ocl (1)
 Reactions: Chlorine
 
octahedral (1)
 Compounds: Fluorine
 
octaoxide (1)
 Reactions: Uranium
 
octaves (2)
 On This Day... 26 November
 On This Day... 7 February
 
october (45)
 Biography: Carl Gustav Mosander
 Biography: Clemens Alexander Winkler
 Biography: Dirk Coster
 Biography: Fausto de Elhuyar y de Suvisa
 Biography: Franz-Joseph Muller Freiherr von Reichenstein
 Biography: Gustav Robert Kirchhoff
 Biography: Henry Cavendish
 Biography: Johann August Arfvedson
 Biography: Julius Caesar Scaliger
 Biography: Lise Meitner
 Biography: Marguerite Catherine Perey
 Biography: Pierre Jules César Janssen
 Biography: Sir William Ramsay
 Data1: Helium
 On This Day... 1 October
 On This Day... 10 October
 On This Day... 11 October
 On This Day... 12 October
 On This Day... 13 October
 On This Day... 14 October
 On This Day... 15 October
 On This Day... 16 October
 On This Day... 17 October
 On This Day... 18 October
 On This Day... 19 October
 On This Day... 2 October
 On This Day... 20 October
 On This Day... 21 October
 On This Day... 22 October
 On This Day... 23 October
 On This Day... 24 October
 On This Day... 25 October
 On This Day... 26 October
 On This Day... 27 October
 On This Day... 28 October
 On This Day... 29 October
 On This Day... 3 October
 On This Day... 30 October
 On This Day... 31 October
 On This Day... 4 October
 On This Day... 5 October
 On This Day... 6 October
 On This Day... 7 October
 On This Day... 8 October
 On This Day... 9 October
 
odd (2)
 Glossary: Element
 Production: Holmium
 
oddo (1)
 Production: Holmium
 
odor (1)
 Compounds: Nitrogen
 
odors (1)
 Compounds: Sodium
 
odour (9)
 Allotrope: Oxygen
 Biography: Antoine-Jerome Balard
 Biography: Robert Wilhelm Bunsen
 Compounds: Nitrogen
 Data1: Chlorine
 Data1: Fluorine
 Data1: Iodine
 Data1: Osmium
 Data1: Tellurium
 
odourless (1)
 Data1: Hydrogen
 
odours (2)
 Compounds: Sodium
 Glossary: Aromatic
 
oersted (5)
 Biography: Hans Christian Oersted
 Biography: Sir Humphry Davy
 Biography: William Hyde Wollaston
 Data1: Aluminium
 On This Day... 14 August
 
of2 (2)
 Data2: Rhodium
 Reactions: Fluorine
 
offer (2)
 Data1: Europium
 Isotope: Helium
 
offered (6)
 Biography: Emilio Gino Segre
 Biography: Hans Christian Oersted
 Biography: Ida Eva Tacke Noddack
 Biography: Pierre Curie
 Data1: Neodymium
 On This Day... 22 February
 
offers (2)
 Biography: Karl Wilhelm Scheele
 Data1: Helium
 
official (8)
 Data1: Bohrium
 Data1: Dubnium
 Data1: Hassium
 Data1: Meitnerium
 Data1: Niobium
 Data1: Rutherfordium
 Data1: Samarium
 Data1: Seaborgium
 
officially (4)
 Biography: Joseph Priestley
 Data1: Darmstadtium
 Data1: Francium
 Data1: Niobium
 
officials (1)
 Data1: Technetium
 
offset (1)
 Data1: Hydrogen
 
oftern (1)
 Compounds: Bromine
 
oganessian (1)
 Data1: Bohrium
 
ogawa (2)
 Data1: Rhenium
 Data1: Technetium
 
oh (92)
 Compounds: Aluminium
 Compounds: Calcium
 Compounds: Magnesium
 Compounds: Nickel
 Compounds: Plutonium
 Compounds: Zinc
 Compounds: Zirconium
 Country: Canada
 Data1: Caesium
 Data1: Cerium
 Data1: Copper
 Data1: Lithium
 Data1: Magnesium
 Data1: Nickel
 Data1: Niobium
 Data1: Phosphorus
 Data1: Rubidium
 Data1: Terbium
 Data2: Hydrogen
 Data2: Oxygen
 Document: The Alkaline Earth Metals (Group 2)
 Equation: Base ionisation constant
 Production: Beryllium
 Production: Cerium
 Production: Copper
 Production: Hydrogen
 Production: Lithium
 Production: Magnesium
 Production: Nickel
 Production: Terbium
 Reactions: Aluminium
 Reactions: Arsenic
 Reactions: Barium
 Reactions: Beryllium
 Reactions: Bismuth
 Reactions: Boron
 Reactions: Bromine
 Reactions: Cadmium
 Reactions: Calcium
 Reactions: Carbon
 Reactions: Cerium
 Reactions: Chlorine
 Reactions: Chromium
 Reactions: Cobalt
 Reactions: Dysprosium
 Reactions: Erbium
 Reactions: Europium
 Reactions: Fluorine
 Reactions: Gadolinium
 Reactions: Gallium
 Reactions: Hafnium
 Reactions: Holmium
 Reactions: Hydrogen
 Reactions: Indium
 Reactions: Iodine
 Reactions: Iridium
 Reactions: Iron
 Reactions: Lanthanum
 Reactions: Lead
 Reactions: Lutetium
 Reactions: Magnesium
 Reactions: Manganese
 Reactions: Mercury
 Reactions: Molybdenum
 Reactions: Neodymium
 Reactions: Nickel
 Reactions: Nitrogen
 Reactions: Osmium
 Reactions: Oxygen
 Reactions: Palladium
 Reactions: Platinum
 Reactions: Plutonium
 Reactions: Praseodymium
 Reactions: Radium
 Reactions: Rhenium
 Reactions: Samarium
 Reactions: Scandium
 Reactions: Selenium
 Reactions: Silver
 Reactions: Strontium
 Reactions: Sulfur
 Reactions: Tellurium
 Reactions: Terbium
 Reactions: Thallium
 Reactions: Thorium
 Reactions: Thulium
 Reactions: Uranium
 Reactions: Vanadium
 Reactions: Ytterbium
 Reactions: Yttrium
 Reactions: Zinc
 Reactions: Zirconium
 
ohio (1)
 Data1: Phosphorus
 
ohm (3)
 Compounds: Zirconium
 Glossary: Electrical Resistivity
 On This Day... 16 March
 
oi (1)
 Reactions: Iodine
 
oid (2)
 Glossary: Actinides
 Glossary: Lanthanides (old name)
 
oil (26)
 Biography: Dmitriy Ivanovich Mendeleyev
 Compounds: Carbon
 Compounds: Chlorine
 Compounds: Cobalt
 Compounds: Copper
 Compounds: Fluorine
 Compounds: Molybdenum
 Compounds: Sodium
 Compounds: Sulfur
 Country: United States of America
 Data1: Bromine
 Data1: Californium
 Data1: Hydrogen
 Data1: Molybdenum
 Data1: Nitrogen
 Data1: Potassium
 Data1: Sodium
 Data1: Thallium
 Data1: Vanadium
 Document: The Alkali (Group 1) Metals
 Glossary: Magnetic Ordering
 Glossary: Viscosity
 Production: Carbon
 Production: Copper
 Production: Sulfur
 Production: Vanadium
 
oils (8)
 Allotrope: Phosphorus
 Compounds: Molybdenum
 Compounds: Sodium
 Data1: Calcium
 Data1: Hydrogen
 Data1: Silicon
 Glossary: Acid
 On This Day... 27 March
 
oily (2)
 Compounds: Nitrogen
 Compounds: Selenium
 
ointment (2)
 Compounds: Zinc
 Data1: Zinc
 
ointments (1)
 Data1: Mercury
 
ois (1)
 On This Day... 10 May
 
oklahoma (1)
 Data1: Nitrogen
 
oklo (1)
 Production: Plutonium
 
oksygen (1)
 Names: Oxygen
 
olah (1)
 On This Day... 22 May
 
older (2)
 Data1: Gadolinium
 Production: Aluminium
 
oldest (5)
 Compounds: Lead
 Data1: Copper
 Data1: Lead
 Glossary: Magnetic Ordering
 Isotope: Magnesium
 
oleum (1)
 Reactions: Tantalum
 
olga (1)
 Biography: Dmitriy Ivanovich Mendeleyev
 
oliver (1)
 On This Day... 21 February
 
olivine (2)
 Data1: Magnesium
 Production: Magnesium
 
ollaborator (1)
 On This Day... 20 January
 
olmio (1)
 Names: Holmium
 
olovo (1)
 Names: Lead
 
olszewski (2)
 Data1: Oxygen
 On This Day... 28 October
 
olympic (2)
 Country: Australia
 Production: Uranium
 
oman (1)
 Country: Oman
 
omnipresent (1)
 Biography: Walter Noddack
 
onc (1)
 Compounds: Mercury
 
once (29)
 Biography: Jöns Jacob Berzelius
 Biography: Robert Wilhelm Bunsen
 Compounds: Chromium
 Compounds: Samarium
 Compounds: Sodium
 Data1: Aluminium
 Data1: Europium
 Data1: Iodine
 Data1: Krypton
 Data1: Magnesium
 Data1: Mercury
 Data1: Radon
 Data1: Thallium
 Data1: Tin
 Document: The Lanthanoid Series
 Document: Understanding Electron Configuration Tables
 Glossary: Energy Levels
 Glossary: Enthalpy Change of Fusion (Heat of Fusion)
 Glossary: Fahrenheit
 Glossary: Superconducting temperature
 Production: Aluminium
 Production: Copper
 Production: Iron
 Production: Mercury
 Reactions: Barium
 Reactions: Calcium
 Reactions: Magnesium
 Reactions: Strontium
 Reactions: Titanium
 
one (231)
 Allotrope: Carbon
 Biography: (Gabriel) Daniel Fahrenheit
 Biography: Antoine-Laurent de Lavoisier
 Biography: Baron Axel Fredrik Cronstedt
 Biography: Dmitriy Ivanovich Mendeleyev
 Biography: Ferdinand Frederic Henri Moissan
 Biography: Henry Cavendish
 Biography: Ida Eva Tacke Noddack
 Biography: Irene Joliot-Curie
 Biography: Jöns Jacob Berzelius
 Biography: Julius Caesar Scaliger
 Biography: Karl Wilhelm Scheele
 Biography: Louis Jacques Thenard
 Biography: Michael Faraday
 Biography: Philip Hauge Abelson
 Biography: Pierre Curie
 Biography: Pierre Jules César Janssen
 Biography: Robert Wilhelm Bunsen
 Biography: Sir Humphry Davy
 Biography: Sir William Crookes
 Biography: Smithson Tennant
 Biography: William Hyde Wollaston
 Compounds: Boron
 Compounds: Cadmium
 Compounds: Chlorine
 Compounds: Lead
 Compounds: Lithium
 Compounds: Nitrogen
 Compounds: Potassium
 Compounds: Sodium
 Compounds: Tantalum
 Compounds: Zinc
 Compounds: Zirconium
 Country: Australia
 Country: Brazil
 Country: Burkina Faso
 Country: Canada
 Country: Chile
 Country: China
 Country: Egypt
 Country: Germany
 Country: Jamaica
 Country: Madagascar
 Country: Mexico
 Country: Mozambique
 Country: Norway
 Country: Outer space
 Country: Peru
 Country: Poland
 Country: Republic of Korea
 Country: Russia
 Country: Uganda
 Country: Ukraine
 Country: United States of America
 Country: Zambia
 Data1: Actinium
 Data1: Aluminium
 Data1: Arsenic
 Data1: Astatine
 Data1: Berkelium
 Data1: Bismuth
 Data1: Bohrium
 Data1: Caesium
 Data1: Californium
 Data1: Carbon
 Data1: Cerium
 Data1: Chromium
 Data1: Copper
 Data1: Curium
 Data1: Darmstadtium
 Data1: Dubnium
 Data1: Francium
 Data1: Gadolinium
 Data1: Gallium
 Data1: Germanium
 Data1: Gold
 Data1: Hassium
 Data1: Helium
 Data1: Holmium
 Data1: Hydrogen
 Data1: Indium
 Data1: Iodine
 Data1: Iron
 Data1: Krypton
 Data1: Lanthanum
 Data1: Lithium
 Data1: Lutetium
 Data1: Manganese
 Data1: Meitnerium
 Data1: Mendelevium
 Data1: Mercury
 Data1: Neodymium
 Data1: Neon
 Data1: Nitrogen
 Data1: Osmium
 Data1: Palladium
 Data1: Phosphorus
 Data1: Plutonium
 Data1: Polonium
 Data1: Radon
 Data1: Roentgenium
 Data1: Ruthenium
 Data1: Rutherfordium
 Data1: Samarium
 Data1: Scandium
 Data1: Seaborgium
 Data1: Silicon
 Data1: Sodium
 Data1: Thorium
 Data1: Thulium
 Data1: Tin
 Data1: Tungsten
 Data1: Ununhexium
 Data1: Ununoctium
 Data1: Ununpentium
 Data1: Ununquadium
 Data1: Ununseptium
 Data1: Ununtrium
 Data1: Uranium
 Data1: Vanadium
 Data1: Xenon
 Data1: Ytterbium
 Data1: Yttrium
 Data1: Zinc
 Document: The Alkali (Group 1) Metals
 Document: The Halogens (Group 17)
 Document: The Transition Metals (Groups 3 to 12)
 Document: Understanding Electron Configuration Tables
 Equation: Avogadro's law
 Equation: Graham's Law
 Glossary:
 Glossary: Actinides
 Glossary: Alkali Metal
 Glossary: Allotrope
 Glossary: Alloy
 Glossary: Alpha Decay
 Glossary: Aqua regia
 Glossary: Atom
 Glossary: Atomic Charge
 Glossary: Atomic Mass
 Glossary: Atomic Radius
 Glossary: Avogadro's Constant
 Glossary: Brinell Hardness
 Glossary: Double Beta Decay
 Glossary: Double Electron Capture
 Glossary: Doubly Magic
 Glossary: Electron
 Glossary: Electron Capture
 Glossary: Electron Volt
 Glossary: Electronegativity
 Glossary: Element
 Glossary: Emission Spectrum
 Glossary: Gamma Ray
 Glossary: Group
 Glossary: Half Life
 Glossary: Halogens
 Glossary: Ideal Gas
 Glossary: Ion
 Glossary: Ionization Potential
 Glossary: Island of Stability
 Glossary: Isometric Transition
 Glossary: Isotope
 Glossary: Lanthanides (old name)
 Glossary: Magic Number
 Glossary: Magnetic Ordering
 Glossary: Moh's Scale of Hardness
 Glossary: Mole
 Glossary: Molecule
 Glossary: Neutrino
 Glossary: Neutron
 Glossary: Noble Gasses (inert gasses)
 Glossary: Nucleus
 Glossary: Periods
 Glossary: pH
 Glossary: Poisson Ratio
 Glossary: Proton
 Glossary: Shear Modulus
 Glossary: Transactinides
 Glossary: van der Waals radius
 Glossary: Vickers Hardness
 Isotope: Beryllium
 Isotope: Bismuth
 Isotope: Cobalt
 Isotope: Helium
 Isotope: Hydrogen
 Isotope: Iodine
 Isotope: Lithium
 Isotope: Radium
 Isotope: Technetium
 Isotope: Tungsten
 On This Day... 19 February
 On This Day... 20 July
 On This Day... 25 February
 On This Day... 26 June
 On This Day... 29 June
 Production: Astatine
 Production: Berkelium
 Production: Cadmium
 Production: Caesium
 Production: Copper
 Production: Curium
 Production: Francium
 Production: Gold
 Production: Helium
 Production: Hydrogen
 Production: Iron
 Production: Lead
 Production: Lutetium
 Production: Mendelevium
 Production: Neptunium
 Production: Nickel
 Production: Palladium
 Production: Plutonium
 Production: Radium
 Production: Radon
 Production: Rubidium
 Production: Ruthenium
 Production: Silicon
 Production: Silver
 Production: Tantalum
 Production: Technetium
 Production: Uranium
 Production: Xenon
 Production: Zinc
 Reactions: Bromine
 Reactions: Chlorine
 Reactions: Iodine
 Reactions: Palladium
 Reactions: Phosphorus
 Reactions: Platinum
 Reactions: Uranium
 
ones (4)
 Biography: Joseph Priestley
 Compounds: Oxygen
 Production: Aluminium
 Production: Radon
 
ongoing (1)
 Country: Democratic Republic of Congo
 
onnes (1)
 Data1: Helium
 
onsager (1)
 On This Day... 27 November
 
ontaria (1)
 Country: Canada
 
ontario (11)
 Country: Canada
 Data1: Osmium
 Data1: Palladium
 Data1: Rhodium
 Production: Nickel
 Production: Osmium
 Production: Palladium
 Production: Platinum
 Production: Radium
 Production: Rhodium
 Production: Ruthenium
 
onto (15)
 Biography: Irene Joliot-Curie
 Compounds: Argon
 Compounds: Copper
 Compounds: Gadolinium
 Compounds: Indium
 Compounds: Iron
 Compounds: Selenium
 Data1: Argon
 Data1: Curium
 Data1: Indium
 Data1: Phosphorus
 Data1: Roentgenium
 Production: Curium
 Production: Plutonium
 Production: Technetium
 
onward (1)
 Data1: Samarium
 
onwards (1)
 Production: Technetium
 
opacifier (1)
 Compounds: Titanium
 
opacifying (1)
 Compounds: Antimony
 
opacity (1)
 Compounds: Titanium
 
opal (2)
 Compounds: Silicon
 Production: Silicon
 
opalescent (1)
 Compounds: Fluorine
 
opaque (1)
 Glossary: Allotrope
 
opec (1)
 Production: Copper
 
open (8)
 Compounds: Calcium
 Compounds: Chlorine
 Compounds: Sodium
 Country: Norway
 Production: Copper
 Production: Gold
 Production: Radon
 Production: Uranium
 
opened (5)
 Biography: Gottfried Münzenberg
 Country: Norway
 Data1: Germanium
 On This Day... 30 October
 Production: Iron
 
opening (2)
 Country: United Kingdom
 Data1: Potassium
 
operable (1)
 On This Day... 11 July
 
operate (3)
 Compounds: Silicon
 Data1: Yttrium
 Production: Aluminium
 
operated (4)
 Compounds: Arsenic
 Compounds: Gallium
 Data1: Lanthanum
 Data1: Yttrium
 
operating (1)
 Compounds: Aluminium
 
operation (13)
 Compounds: Silicon
 Country: Algeria
 Country: Canada
 Country: United States of America
 Data1: Einsteinium
 Data1: Fermium
 Data1: Osmium
 Data1: Phosphorus
 Equation: Boyle's Law
 Isotope: Xenon
 Production: Fermium
 Production: Potassium
 Production: Radon
 
operational (1)
 Production: Aluminium
 
operations (5)
 Biography: Irene Joliot-Curie
 Compounds: Sodium
 Data1: Neodymium
 Data1: Sulfur
 Data1: Thulium
 
operative (1)
 Biography: Irene Joliot-Curie
 
opinion (1)
 Biography: Hans Christian Oersted
 
opinions (1)
 Biography: Joseph Priestley
 
opium (2)
 Biography: Bernard Courtois
 On This Day... 13 January
 
opportunity (2)
 Biography: Robert Wilhelm Bunsen
 Biography: William Hyde Wollaston
 
opposed (9)
 Biography: Joseph Priestley
 Data1: Antimony
 Data1: Bohrium
 Data1: Francium
 Glossary: Magnetic Ordering
 On This Day... 8 November
 Production: Arsenic
 Production: Lanthanum
 Production: Silicon
 
opposes (1)
 Glossary: Electrical Resistivity
 
opposing (1)
 Glossary: Magnetic Ordering
 
opposite (8)
 Allotrope: Carbon
 Biography: Pierre Curie
 Glossary: Absorption Spectrum
 Glossary: Antimatter
 Glossary: Base
 Glossary: Enthalpy Change of Vapourisation
 Glossary: Magnetic Ordering
 Glossary: Vickers Hardness
 
opposites (1)
 Glossary: Base
 
optic (3)
 Compounds: Cadmium
 Compounds: Zinc
 Production: Francium
 
optical (37)
 Compounds: Erbium
 Compounds: Gadolinium
 Compounds: Germanium
 Compounds: Hafnium
 Compounds: Indium
 Compounds: Lithium
 Compounds: Neon
 Compounds: Scandium
 Compounds: Tantalum
 Compounds: Titanium
 Compounds: Ytterbium
 Data1: Gadolinium
 Data1: Gallium
 Data1: Niobium
 Data1: Samarium
 Data1: Strontium
 Data2: Argon
 Data2: Arsenic
 Data2: Bromine
 Data2: Carbon
 Data2: Chlorine
 Data2: Fluorine
 Data2: Helium
 Data2: Hydrogen
 Data2: Krypton
 Data2: Mercury
 Data2: Neon
 Data2: Nitrogen
 Data2: Oxygen
 Data2: Phosphorus
 Data2: Selenium
 Data2: Sulfur
 Data2: Tellurium
 Data2: Xenon
 Data2: Zinc
 Glossary: Temperature
 On This Day... 27 December
 
optics (8)
 Allotrope: Carbon
 Biography: John William Strutt Rayleigh
 Biography: William Hyde Wollaston
 Compounds: Fluorine
 Compounds: Lithium
 Data1: Germanium
 Data1: Strontium
 Production: Boron
 
options (1)
 Production: Technetium
 
optoelectronics (1)
 Compounds: Cadmium
 
oral (1)
 Compounds: Magnesium
 
orally (4)
 Biography: John Dalton
 Compounds: Gold
 Data1: Chromium
 Data1: Molybdenum
 
orange (16)
 Allotrope: Sulfur
 Compounds: Aluminium
 Compounds: Indium
 Compounds: Iodine
 Compounds: Nitrogen
 Compounds: Phosphorus
 Compounds: Vanadium
 Data1: Chromium
 Data1: Molybdenum
 Data1: Neodymium
 Data1: Neon
 Data1: Praseodymium
 Data1: Radon
 On This Day... 30 October
 Reactions: Potassium
 Reactions: Sodium
 
oranges (1)
 Data1: Molybdenum
 
oration (1)
 Biography: Julius Caesar Scaliger
 
orations (1)
 Biography: Julius Caesar Scaliger
 
orbital (15)
 Document: The Transition Metals (Groups 3 to 12)
 Glossary: Actinides
 Glossary: Actinoids
 Glossary: Double Beta Decay
 Glossary: Double Electron Capture
 Glossary: Electron Capture
 Glossary: Group
 Glossary: Lanthanides (old name)
 Glossary: Lanthanoids
 Glossary: Magnetic Ordering
 Glossary: Orbital
 Glossary: Periodic Table
 On This Day... 18 July
 On This Day... 4 February
 On This Day... 7 June
 
orbitals (4)
 Data1: Copper
 Document: The Transition Metals (Groups 3 to 12)
 Glossary: Absorption Spectrum
 Glossary: Periodic Table
 
order (24)
 Allotrope: Carbon
 Allotrope: Oxygen
 Biography: Charles Hatchett
 Biography: Robert Wilhelm Bunsen
 Compounds: Tin
 Country: Canada
 Data1: Lawrencium
 Data1: Niobium
 Data1: Plutonium
 Data1: Scandium
 Glossary: Double Beta Decay
 Glossary: Endothermic
 Glossary: Enthalpy Change of Fusion (Heat of Fusion)
 Glossary: Gamma Ray
 Glossary: Group
 Glossary: Magnetic Ordering
 Glossary: Molecule
 Glossary: Periodic Law
 Glossary: Radiation
 Glossary: Temperature
 Isotope: Helium
 On This Day... 7 February
 Production: Potassium
 Production: Technetium
 
ordered (1)
 Glossary: Enthalpy Change of Fusion (Heat of Fusion)
 
ordering (111)
 Data2: Actinium
 Data2: Aluminium
 Data2: Americium
 Data2: Antimony
 Data2: Argon
 Data2: Arsenic
 Data2: Astatine
 Data2: Barium
 Data2: Berkelium
 Data2: Beryllium
 Data2: Bismuth
 Data2: Bohrium
 Data2: Boron
 Data2: Bromine
 Data2: Cadmium
 Data2: Caesium
 Data2: Calcium
 Data2: Californium
 Data2: Carbon
 Data2: Cerium
 Data2: Chlorine
 Data2: Chromium
 Data2: Cobalt
 Data2: Copper
 Data2: Curium
 Data2: Darmstadtium
 Data2: Dysprosium
 Data2: Einsteinium
 Data2: Erbium
 Data2: Europium
 Data2: Fermium
 Data2: Fluorine
 Data2: Francium
 Data2: Gadolinium
 Data2: Gallium
 Data2: Germanium
 Data2: Gold
 Data2: Hafnium
 Data2: Hassium
 Data2: Helium
 Data2: Holmium
 Data2: Hydrogen
 Data2: Indium
 Data2: Iodine
 Data2: Iridium
 Data2: Iron
 Data2: Krypton
 Data2: Lanthanum
 Data2: Lawrencium
 Data2: Lead
 Data2: Lithium
 Data2: Lutetium
 Data2: Magnesium
 Data2: Manganese
 Data2: Meitnerium
 Data2: Mendelevium
 Data2: Mercury
 Data2: Molybdenum
 Data2: Neodymium
 Data2: Neon
 Data2: Neptunium
 Data2: Nickel
 Data2: Niobium
 Data2: Nitrogen
 Data2: Nobelium
 Data2: Osmium
 Data2: Oxygen
 Data2: Palladium
 Data2: Phosphorus
 Data2: Platinum
 Data2: Plutonium
 Data2: Polonium
 Data2: Potassium
 Data2: Praseodymium
 Data2: Promethium
 Data2: Protactinium
 Data2: Radium
 Data2: Radon
 Data2: Rhenium
 Data2: Rhodium
 Data2: Roentgenium
 Data2: Rubidium
 Data2: Ruthenium
 Data2: Rutherfordium
 Data2: Samarium
 Data2: Scandium
 Data2: Seaborgium
 Data2: Selenium
 Data2: Silicon
 Data2: Silver
 Data2: Sodium
 Data2: Strontium
 Data2: Sulfur
 Data2: Tantalum
 Data2: Technetium
 Data2: Tellurium
 Data2: Terbium
 Data2: Thallium
 Data2: Thorium
 Data2: Thulium
 Data2: Tin
 Data2: Titanium
 Data2: Tungsten
 Data2: Uranium
 Data2: Vanadium
 Data2: Xenon
 Data2: Ytterbium
 Data2: Yttrium
 Data2: Zinc
 Data2: Zirconium
 Glossary: Magnetic Ordering
 
orders (4)
 Biography: Julius Caesar Scaliger
 Data1: Indium
 Equation: Acid dissociation constant
 Equation: Base ionisation constant
 
ordinal (1)
 Glossary: Moh's Scale of Hardness
 
ordinary (15)
 Allotrope: Oxygen
 Biography: (Gabriel) Daniel Fahrenheit
 Biography: Pierre Jules César Janssen
 Compounds: Fluorine
 Country: Oceans / Seas
 Country: Outer space
 Data1: Gold
 Data1: Neon
 Data1: Radon
 Data1: Sulfur
 Data1: Thallium
 Glossary: Heavy water (D2O)
 Glossary: Moh's Scale of Hardness
 Glossary: Temperature
 Production: Mercury
 
ordnance (3)
 Compounds: Dysprosium
 Compounds: Terbium
 On This Day... 17 July
 
ore (106)
 Biography: Clemens Alexander Winkler
 Biography: Dirk Coster
 Biography: Franz-Joseph Muller Freiherr von Reichenstein
 Biography: William Hyde Wollaston
 Compounds: Radium
 Compounds: Sodium
 Compounds: Sulfur
 Country: Algeria
 Country: Australia
 Country: Austria
 Country: Azerbaijan
 Country: Bhutan
 Country: Bosnia and Herzegovina
 Country: Brazil
 Country: Canada
 Country: Chile
 Country: China
 Country: Colombia
 Country: Cuba
 Country: Czech Republic
 Country: Democratic People's Republic of Korea
 Country: Democratic Republic of Congo
 Country: Egypt
 Country: Germany
 Country: Ghana
 Country: Guinea
 Country: India
 Country: Indonesia
 Country: Iran
 Country: Jamaica
 Country: Kazakhstan
 Country: Malaysia
 Country: Mauritania
 Country: Mexico
 Country: New Zealand
 Country: Nigeria
 Country: Norway
 Country: Pakistan
 Country: Peru
 Country: Republic of Korea
 Country: Russia
 Country: South Africa
 Country: Spain
 Country: Sweden
 Country: Thailand
 Country: Tunisia
 Country: Turkey
 Country: Ukraine
 Country: United Kingdom
 Country: United States of America
 Country: Venezuela
 Country: Vietnam
 Country: Zimbabwe
 Data1: Aluminium
 Data1: Boron
 Data1: Cerium
 Data1: Chromium
 Data1: Cobalt
 Data1: Gold
 Data1: Lead
 Data1: Lithium
 Data1: Lutetium
 Data1: Manganese
 Data1: Molybdenum
 Data1: Nickel
 Data1: Niobium
 Data1: Osmium
 Data1: Palladium
 Data1: Protactinium
 Data1: Rhenium
 Data1: Rhodium
 Data1: Samarium
 Data1: Technetium
 Data1: Tin
 Data1: Titanium
 Data1: Tungsten
 On This Day... 13 April
 On This Day... 6 January
 Production: Actinium
 Production: Aluminium
 Production: Antimony
 Production: Boron
 Production: Chromium
 Production: Copper
 Production: Erbium
 Production: Germanium
 Production: Gold
 Production: Indium
 Production: Iron
 Production: Lead
 Production: Lutetium
 Production: Manganese
 Production: Mercury
 Production: Molybdenum
 Production: Nickel
 Production: Niobium
 Production: Palladium
 Production: Platinum
 Production: Protactinium
 Production: Radium
 Production: Rhodium
 Production: Silver
 Production: Tantalum
 Production: Terbium
 Production: Thallium
 Production: Uranium
 
orebodies (1)
 Production: Lanthanum
 
orefield (1)
 Production: Lead
 
oregon (1)
 Production: Nickel
 
ores (108)
 Biography: Ferdinand Reich
 Compounds: Radium
 Country: Albania
 Country: Argentina
 Country: Australia
 Country: Brazil
 Country: Burma (Myanmar)
 Country: Canada
 Country: China
 Country: Cuba
 Country: Democratic Republic of Congo
 Country: Egypt
 Country: Finland
 Country: India
 Country: Iran
 Country: Kazakhstan
 Country: Madagascar
 Country: Malaysia
 Country: Norway
 Country: Oman
 Country: Pakistan
 Country: Peru
 Country: Philippines
 Country: Republic of Korea
 Country: Russia
 Country: Sierra Leone
 Country: South Africa
 Country: Sri Lanka
 Country: Sudan
 Country: Turkey
 Country: Ukraine
 Country: United States of America
 Country: Vietnam
 Country: Zimbabwe
 Data1: Actinium
 Data1: Cadmium
 Data1: Chromium
 Data1: Cobalt
 Data1: Germanium
 Data1: Indium
 Data1: Iron
 Data1: Manganese
 Data1: Mercury
 Data1: Molybdenum
 Data1: Neodymium
 Data1: Neptunium
 Data1: Nickel
 Data1: Osmium
 Data1: Palladium
 Data1: Platinum
 Data1: Plutonium
 Data1: Polonium
 Data1: Protactinium
 Data1: Radium
 Data1: Rhenium
 Data1: Rhodium
 Data1: Ruthenium
 Data1: Scandium
 Data1: Silver
 Data1: Sulfur
 Data1: Tantalum
 Data1: Technetium
 Data1: Tin
 Data1: Titanium
 Data1: Uranium
 Data1: Vanadium
 Data1: Yttrium
 Data1: Zinc
 Document: The Actinoid Series
 Glossary: Actinides
 Glossary: Actinoids
 On This Day... 7 March
 Production: Bismuth
 Production: Cadmium
 Production: Chromium
 Production: Cobalt
 Production: Dysprosium
 Production: Erbium
 Production: Gallium
 Production: Germanium
 Production: Holmium
 Production: Indium
 Production: Iron
 Production: Lanthanum
 Production: Magnesium
 Production: Mercury
 Production: Neodymium
 Production: Neptunium
 Production: Osmium
 Production: Palladium
 Production: Platinum
 Production: Plutonium
 Production: Polonium
 Production: Promethium
 Production: Protactinium
 Production: Radium
 Production: Rhenium
 Production: Rhodium
 Production: Ruthenium
 Production: Scandium
 Production: Selenium
 Production: Silver
 Production: Tantalum
 Production: Thallium
 Production: Thulium
 Production: Titanium
 Production: Uranium
 Production: Yttrium
 
organic (54)
 Allotrope: Carbon
 Allotrope: Phosphorus
 Biography: Antoine-Laurent de Lavoisier
 Biography: Friedrich Wöhler
 Biography: Jöns Jacob Berzelius
 Biography: Karl Wilhelm Scheele
 Biography: Robert Wilhelm Bunsen
 Compounds: Arsenic
 Compounds: Calcium
 Compounds: Chlorine
 Compounds: Copper
 Compounds: Fluorine
 Compounds: Indium
 Compounds: Nitrogen
 Compounds: Palladium
 Data1: Bromine
 Data1: Carbon
 Data1: Chlorine
 Data1: Gadolinium
 Data1: Magnesium
 Data1: Nitrogen
 Data1: Ruthenium
 Data1: Selenium
 Data1: Tin
 Data2: Fluorine
 Glossary: Aliphatic
 Glossary: Magnetic Ordering
 Glossary: Organic chemistry
 Isotope: Carbon
 On This Day... 11 September
 On This Day... 13 July
 On This Day... 14 June
 On This Day... 15 March
 On This Day... 17 February
 On This Day... 18 July
 On This Day... 2 March
 On This Day... 22 February
 On This Day... 24 July
 On This Day... 26 March
 On This Day... 27 June
 On This Day... 27 March
 On This Day... 27 May
 On This Day... 28 January
 On This Day... 5 November
 On This Day... 6 April
 On This Day... 6 May
 On This Day... 7 August
 On This Day... 7 September
 On This Day... 9 February
 Production: Arsenic
 Production: Selenium
 Production: Sulfur
 Production: Thorium
 Production: Uranium
 
organics (2)
 Compounds: Oxygen
 Data2: Bromine
 
organism (1)
 Glossary: Alpha Decay
 
organisms (15)
 Compounds: Chlorine
 Compounds: Cobalt
 Compounds: Sodium
 Data1: Arsenic
 Data1: Cadmium
 Data1: Chlorine
 Data1: Cobalt
 Data1: Iron
 Data1: Molybdenum
 Document: The Halogens (Group 17)
 Glossary: Alpha Decay
 Glossary: Halogens
 Production: Hydrogen
 Production: Sulfur
 Production: Uranium
 
organization (4)
 Biography: Sir Humphry Davy
 Compounds: Gold
 Data1: Chromium
 Data1: Neptunium
 
organizations (3)
 Biography: Dmitriy Ivanovich Mendeleyev
 Data1: Niobium
 Data1: Plutonium
 
organized (1)
 On This Day... 3 April
 
organoboron (1)
 On This Day... 22 May
 
organogold (1)
 Compounds: Gold
 
organometallic (2)
 Compounds: Europium
 On This Day... 18 January
 
organophosphate (1)
 Data1: Sodium
 
organozinc (1)
 On This Day... 1 April
 
organs (1)
 Data1: Lead
 
orient (2)
 Data1: Nickel
 Data1: Zinc
 
orientation (1)
 Glossary: Thermal Conductivity
 
orifices (1)
 Compounds: Chromium
 
origin (124)
 Biography: Philip Hauge Abelson
 Biography: Robert Wilhelm Bunsen
 Country: Outer space
 Data1: Actinium
 Data1: Aluminium
 Data1: Americium
 Data1: Antimony
 Data1: Argon
 Data1: Arsenic
 Data1: Astatine
 Data1: Barium
 Data1: Berkelium
 Data1: Beryllium
 Data1: Bismuth
 Data1: Bohrium
 Data1: Boron
 Data1: Bromine
 Data1: Cadmium
 Data1: Caesium
 Data1: Calcium
 Data1: Californium
 Data1: Carbon
 Data1: Cerium
 Data1: Chlorine
 Data1: Chromium
 Data1: Cobalt
 Data1: Copper
 Data1: Curium
 Data1: Darmstadtium
 Data1: Dubnium
 Data1: Dysprosium
 Data1: Einsteinium
 Data1: Erbium
 Data1: Europium
 Data1: Fermium
 Data1: Fluorine
 Data1: Francium
 Data1: Gadolinium
 Data1: Gallium
 Data1: Germanium
 Data1: Gold
 Data1: Hafnium
 Data1: Hassium
 Data1: Helium
 Data1: Holmium
 Data1: Hydrogen
 Data1: Indium
 Data1: Iodine
 Data1: Iridium
 Data1: Iron
 Data1: Krypton
 Data1: Lanthanum
 Data1: Lawrencium
 Data1: Lead
 Data1: Lithium
 Data1: Lutetium
 Data1: Magnesium
 Data1: Manganese
 Data1: Meitnerium
 Data1: Mendelevium
 Data1: Mercury
 Data1: Molybdenum
 Data1: Neodymium
 Data1: Neon
 Data1: Neptunium
 Data1: Nickel
 Data1: Niobium
 Data1: Nitrogen
 Data1: Nobelium
 Data1: Osmium
 Data1: Oxygen
 Data1: Palladium
 Data1: Phosphorus
 Data1: Platinum
 Data1: Plutonium
 Data1: Polonium
 Data1: Potassium
 Data1: Praseodymium
 Data1: Promethium
 Data1: Protactinium
 Data1: Radium
 Data1: Radon
 Data1: Rhenium
 Data1: Rhodium
 Data1: Roentgenium
 Data1: Rubidium
 Data1: Ruthenium
 Data1: Rutherfordium
 Data1: Samarium
 Data1: Scandium
 Data1: Seaborgium
 Data1: Selenium
 Data1: Silicon
 Data1: Silver
 Data1: Sodium
 Data1: Strontium
 Data1: Sulfur
 Data1: Tantalum
 Data1: Technetium
 Data1: Tellurium
 Data1: Terbium
 Data1: Thallium
 Data1: Thorium
 Data1: Thulium
 Data1: Tin
 Data1: Titanium
 Data1: Tungsten
 Data1: Ununbium
 Data1: Ununhexium
 Data1: Ununoctium
 Data1: Ununpentium
 Data1: Ununquadium
 Data1: Ununseptium
 Data1: Ununtrium
 Data1: Uranium
 Data1: Vanadium
 Data1: Xenon
 Data1: Ytterbium
 Data1: Yttrium
 Data1: Zinc
 Data1: Zirconium
 On This Day... 10 December
 On This Day... 24 November
 Production: Lithium
 
original (20)
 Biography: Antoine-Laurent de Lavoisier
 Biography: Ferdinand Reich
 Biography: George Charles de Hevesy
 Biography: Henry Cavendish
 Biography: Louis Jacques Thenard
 Biography: Martin Heinrich Klaproth
 Biography: Robert Wilhelm Bunsen
 Compounds: Fluorine
 Compounds: Radium
 Data1: Hafnium
 Data1: Niobium
 Data1: Promethium
 Data1: Samarium
 Data1: Scandium
 Data1: Terbium
 Data1: Ununhexium
 Data1: Ununoctium
 Glossary: Double Beta Decay
 Production: Holmium
 Production: Yttrium
 
originally (11)
 Compounds: Magnesium
 Country: Czech Republic
 Data1: Francium
 Data1: Lawrencium
 Data1: Lead
 Data1: Nickel
 Data1: Niobium
 Data1: Plutonium
 Data1: Vanadium
 Glossary: Magnetic Ordering
 Production: Radium
 
originate (2)
 Glossary: Gamma Ray
 Production: Gold
 
originated (5)
 Country: United Kingdom
 Data1: Magnesium
 Data1: Samarium
 Data1: Technetium
 Production: Europium
 
originates (1)
 Data1: Magnesium
 
origninally (1)
 Data1: Cerium
 
ornamental (1)
 Compounds: Fluorine
 
ornamentation (1)
 Data1: Gold
 
ornaments (2)
 Data1: Gold
 Data1: Silver
 
ornl (2)
 Data1: Promethium
 Production: Technetium
 
oro (1)
 Names: Gold
 
orogenic (1)
 Production: Mercury
 
orotate (1)
 Data1: Lithium
 
orphan (1)
 Biography: Julius Caesar Scaliger
 
orpiment (2)
 Country: Iran
 Production: Arsenic
 
orsay (3)
 Biography: Irene Joliot-Curie
 Data1: Bismuth
 Isotope: Bismuth
 
orsted (1)
 Data1: Aluminium
 
orthite (1)
 Production: Cerium
 
orthoboric (1)
 Data1: Boron
 
orthochromatic (1)
 On This Day... 16 March
 
orthodox (3)
 Biography: Dmitriy Ivanovich Mendeleyev
 Biography: Irene Joliot-Curie
 Biography: Joseph Priestley
 
orthorhombic (10)
 Allotrope: Phosphorus
 Allotrope: Sulfur
 Allotrope: Uranium
 Data2: Bromine
 Data2: Chlorine
 Data2: Gallium
 Data2: Iodine
 Data2: Neptunium
 Data2: Sulfur
 Data2: Uranium
 
orthovanadate (1)
 Data1: Europium
 
os (9)
 Atomic data: Osmium
 Data1: Osmium
 Data2: Osmium
 Isotope: Iridium
 Isotope: Osmium
 Isotope: Platinum
 Isotope: Rhenium
 Reactions: Osmium
 Spectrum: Osmium
 
os+ (1)
 Atomic data: Osmium
 
os+1 (1)
 Data2: Osmium
 
os+2 (1)
 Data2: Osmium
 
os+3 (1)
 Data2: Osmium
 
os+4 (1)
 Data2: Osmium
 
os+5 (1)
 Data2: Osmium
 
os+6 (1)
 Data2: Osmium
 
os+7 (1)
 Data2: Osmium
 
os+8 (1)
 Data2: Osmium
 
os0 (1)
 Data2: Osmium
 
os2+ (1)
 Reactions: Osmium
 
osann (1)
 Data1: Ruthenium
 
osbr4 (1)
 Reactions: Osmium
 
oscillation (1)
 Glossary: Anti-Neutrino
 
oscl4 (1)
 Reactions: Osmium
 
oscl62 (1)
 Reactions: Osmium
 
oscl63 (1)
 Reactions: Osmium
 
osf5 (1)
 Reactions: Platinum
 
osf6 (1)
 Reactions: Osmium
 
osf7 (1)
 Reactions: Osmium
 
osheroff (1)
 Data1: Helium
 
oskar (2)
 Data1: Actinium
 On This Day... 15 September
 
oslash (2)
 Names: Mercury
 Names: Silver
 
osme (1)
 Data1: Osmium
 
osmij (1)
 Names: Osmium
 
osmio (1)
 Names: Osmium
 
osmiridium (4)
 Compounds: Iridium
 Compounds: Osmium
 Data1: Iridium
 Production: Iridium
 
osmium (22)
 Atomic data: Osmium
 Biography: Smithson Tennant
 Compounds: Iridium
 Compounds: Osmium
 Country: Canada
 Country: Colombia
 Country: Russia
 Country: South Africa
 Data1: Iridium
 Data1: Osmium
 Data1: Ruthenium
 Data1: Tungsten
 Data2: Osmium
 Document: Abundance of the Elements in the Solar System
 Isotope: Osmium
 MAC data: Osmium
 Names: Osmium
 Production: Iridium
 Production: Osmium
 Reactions: Hassium
 Reactions: Osmium
 Spectrum: Osmium
 
osmosis (1)
 On This Day... 24 June
 
osmotic (2)
 Equation: Osmotic pressure
 On This Day... 14 October
 
oso2 (1)
 Reactions: Osmium
 
oso3na (1)
 Compounds: Sodium
 
oso4 (2)
 Data1: Osmium
 Reactions: Osmium
 
oso42 (1)
 Reactions: Osmium
 
osram (2)
 Data1: Osmium
 Data1: Tungsten
 
ossigeno (1)
 Names: Oxygen
 
ostentatious (1)
 Data1: Gold
 
osteogenesis (1)
 Isotope: Strontium
 
osteoporosis (4)
 Compounds: Phosphorus
 Compounds: Sodium
 Compounds: Strontium
 Isotope: Gadolinium
 
osteosarcoma (1)
 Compounds: Samarium
 
otago (1)
 Data1: Gold
 
otal (1)
 Country: New Caledonia
 
othmer (1)
 On This Day... 11 May
 
ottawa (1)
 Data1: Darmstadtium
 
otto (18)
 Biography: Emilio Gino Segre
 Biography: Gottfried Münzenberg
 Biography: Ida Eva Tacke Noddack
 Biography: Lise Meitner
 Biography: Otto Hahn
 Data1: Dubnium
 Data1: Protactinium
 Data1: Rhenium
 Data1: Technetium
 On This Day... 10 July
 On This Day... 11 April
 On This Day... 17 December
 On This Day... 20 November
 On This Day... 22 February
 On This Day... 23 January
 On This Day... 26 January
 On This Day... 27 March
 On This Day... 8 March
 
otzi (1)
 Data1: Copper
 
ought (1)
 Biography: Julius Caesar Scaliger
 
ounce (4)
 Data1: Aluminium
 Data1: Gold
 Production: Gold
 Production: Palladium
 
our (7)
 Biography: Robert Wilhelm Bunsen
 Country: Outer space
 Isotope: Aluminium
 On This Day... 10 December
 On This Day... 16 September
 On This Day... 24 March
 Production: Nitrogen
 
ouro (1)
 Names: Gold
 
outbreak (1)
 Biography: Lise Meitner
 
outdid (1)
 Biography: Albert Ghiorso
 
outdoor (1)
 Compounds: Calcium
 
outer (15)
 Data1: Mercury
 Data1: Plutonium
 Data1: Tellurium
 Document: The Halogens (Group 17)
 Glossary: Air
 Glossary: Alkali Metal
 Glossary: Electron Capture
 Glossary: Group
 Glossary: Halogens
 Glossary: Noble Gasses (inert gasses)
 Glossary: Periods
 Glossary: Transactinides
 Production: Neon
 Production: Uranium
 Production: Yttrium
 
outermost (6)
 Document: The Alkali (Group 1) Metals
 Document: The Alkaline Earth Metals (Group 2)
 Document: The Noble Gases (Group 18)
 Glossary: Alkali Metal
 Glossary: Alkali Metal (alkaline-earth metals)
 Glossary: Noble Gasses (inert gasses)
 
outlawed (1)
 Compounds: Phosphorus
 
outline (1)
 Biography: Julius Caesar Scaliger
 
output (15)
 Country: Algeria
 Country: China
 Country: Germany
 Country: Hungary
 Country: Japan
 Country: Kazakhstan
 Country: Qatar
 Country: Russia
 Country: Slovakia
 Country: Ukraine
 Country: United Kingdom
 Country: United States of America
 Production: Gold
 Production: Lead
 Production: Zinc
 
outside (7)
 Biography: Robert Wilhelm Bunsen
 Compounds: Iodine
 Compounds: Nitrogen
 Data1: Berkelium
 Data1: Nobelium
 Data1: Protactinium
 Data1: Titanium
 
outstanding (5)
 Biography: Enrico Fermi
 Biography: Robert Wilhelm Bunsen
 Country: United Kingdom
 On This Day... 14 February
 Production: Europium
 
outward (1)
 Glossary: Temperature
 
oven (2)
 Data1: Chromium
 Data1: Rhenium
 
ovens (2)
 Compounds: Cerium
 Data1: Zinc
 
over (65)
 Biography: Arthur Jeffrey Dempster
 Biography: Dmitriy Ivanovich Mendeleyev
 Biography: Jöns Jacob Berzelius
 Biography: Julius Caesar Scaliger
 Biography: Philip Hauge Abelson
 Biography: Pierre Curie
 Biography: Robert Wilhelm Bunsen
 Biography: Sir Humphry Davy
 Biography: Smithson Tennant
 Compounds: Barium
 Compounds: Copper
 Compounds: Magnesium
 Compounds: Radium
 Country: Peru
 Country: South Africa
 Country: Spain
 Country: Ukraine
 Country: United States of America
 Data1: Antimony
 Data1: Bismuth
 Data1: Calcium
 Data1: Chlorine
 Data1: Chromium
 Data1: Copper
 Data1: Dubnium
 Data1: Einsteinium
 Data1: Hafnium
 Data1: Hydrogen
 Data1: Iodine
 Data1: Magnesium
 Data1: Molybdenum
 Data1: Neon
 Data1: Nickel
 Data1: Phosphorus
 Data1: Radium
 Data1: Rhodium
 Data1: Rubidium
 Data1: Rutherfordium
 Data1: Scandium
 Data1: Titanium
 Data1: Xenon
 Data1: Zinc
 Equation: Acid dissociation constant
 Equation: Base ionisation constant
 Glossary: Absorption Spectrum
 Glossary: Emission Spectrum
 Glossary: Half Life
 Glossary: X-Rays
 Isotope: Bismuth
 Isotope: Boron
 Isotope: Osmium
 Isotope: Radium
 On This Day... 12 January
 Production: Aluminium
 Production: Antimony
 Production: Einsteinium
 Production: Gold
 Production: Helium
 Production: Indium
 Production: Lead
 Production: Magnesium
 Production: Manganese
 Production: Mercury
 Reactions: Silicon
 Reactions: Uranium
 
overabundance (1)
 Production: Krypton
 
overall (5)
 Compounds: Iodine
 Compounds: Nitrogen
 Country: United States of America
 Data1: Radon
 Data1: Sodium
 
overcome (2)
 Biography: Jöns Jacob Berzelius
 Biography: Julius Caesar Scaliger
 
overheating (1)
 Data1: Dysprosium
 
overlap (1)
 Data1: Aluminium
 
overloading (1)
 Glossary: Brinell Hardness
 
overlying (1)
 Data1: Sulfur
 
overseen (1)
 Data1: Fermium
 
overseer (1)
 Biography: Franz-Joseph Muller Freiherr von Reichenstein
 
overshadowed (1)
 Data1: Dysprosium
 
oversupply (1)
 Data1: Samarium
 
overtaking (1)
 Biography: Robert Wilhelm Bunsen
 
owen (4)
 Biography: Emilio Gino Segre
 Glossary: Antiproton
 On This Day... 10 July
 On This Day... 18 October
 
owens (1)
 On This Day... 19 October
 
owing (5)
 Biography: (Gabriel) Daniel Fahrenheit
 Biography: Karl Wilhelm Scheele
 Data1: Copper
 Data1: Selenium
 Isotope: Bismuth
 
owned (2)
 Biography: Dmitriy Ivanovich Mendeleyev
 Data1: Cerium
 
owner (3)
 Biography: Antoine-Laurent de Lavoisier
 Biography: Jöns Jacob Berzelius
 Data1: Cerium
 
owners (1)
 Compounds: Nitrogen
 
oxalic (3)
 Biography: Joseph Louis Gay-Lussac
 Data2: Silver
 Glossary: Acid
 
oxaliplatin (1)
 Compounds: Platinum
 
oxford (4)
 Biography: Frederick Soddy
 Biography: Sir William Crookes
 Data1: Uranium
 On This Day... 24 November
 
oxidation (128)
 Allotrope: Carbon
 Biography: Michael Faraday
 Compounds: Praseodymium
 Compounds: Sodium
 Compounds: Vanadium
 Data1: Argon
 Data1: Cerium
 Data1: Copper
 Data1: Tellurium
 Data2: Actinium
 Data2: Aluminium
 Data2: Americium
 Data2: Antimony
 Data2: Argon
 Data2: Arsenic
 Data2: Astatine
 Data2: Barium
 Data2: Berkelium
 Data2: Beryllium
 Data2: Bismuth
 Data2: Bohrium
 Data2: Boron
 Data2: Bromine
 Data2: Cadmium
 Data2: Caesium
 Data2: Calcium
 Data2: Californium
 Data2: Carbon
 Data2: Cerium
 Data2: Chlorine
 Data2: Chromium
 Data2: Cobalt
 Data2: Copper
 Data2: Curium
 Data2: Dubnium
 Data2: Dysprosium
 Data2: Einsteinium
 Data2: Erbium
 Data2: Europium
 Data2: Fermium
 Data2: Fluorine
 Data2: Francium
 Data2: Gadolinium
 Data2: Gallium
 Data2: Germanium
 Data2: Gold
 Data2: Hafnium
 Data2: Hassium
 Data2: Holmium
 Data2: Hydrogen
 Data2: Indium
 Data2: Iodine
 Data2: Iridium
 Data2: Iron
 Data2: Krypton
 Data2: Lanthanum
 Data2: Lawrencium
 Data2: Lead
 Data2: Lithium
 Data2: Lutetium
 Data2: Magnesium
 Data2: Manganese
 Data2: Meitnerium
 Data2: Mendelevium
 Data2: Mercury
 Data2: Molybdenum
 Data2: Neodymium
 Data2: Neptunium
 Data2: Nickel
 Data2: Niobium
 Data2: Nitrogen
 Data2: Nobelium
 Data2: Osmium
 Data2: Oxygen
 Data2: Palladium
 Data2: Phosphorus
 Data2: Platinum
 Data2: Plutonium
 Data2: Polonium
 Data2: Potassium
 Data2: Praseodymium
 Data2: Promethium
 Data2: Protactinium
 Data2: Radium
 Data2: Radon
 Data2: Rhenium
 Data2: Rhodium
 Data2: Rubidium
 Data2: Ruthenium
 Data2: Rutherfordium
 Data2: Samarium
 Data2: Scandium
 Data2: Seaborgium
 Data2: Selenium
 Data2: Silicon
 Data2: Silver
 Data2: Sodium
 Data2: Strontium
 Data2: Sulfur
 Data2: Tantalum
 Data2: Technetium
 Data2: Tellurium
 Data2: Terbium
 Data2: Thallium
 Data2: Thorium
 Data2: Thulium
 Data2: Tin
 Data2: Titanium
 Data2: Tungsten
 Data2: Uranium
 Data2: Vanadium
 Data2: Xenon
 Data2: Ytterbium
 Data2: Yttrium
 Data2: Zinc
 Data2: Zirconium
 Document: The Transition Metals (Groups 3 to 12)
 Glossary: Oxidation State
 Glossary: Reduction
 On This Day... 1 June
 On This Day... 16 September
 On This Day... 21 October
 On This Day... 28 April
 On This Day... 6 July
 Production: Tellurium
 Reactions: Iron
 Reactions: Rhenium
 Reactions: Technetium
 
oxidative (3)
 Allotrope: Arsenic
 Compounds: Sodium
 Data1: Xenon
 
oxide (153)
 Biography: Antoine-Jerome Balard
 Biography: Carl Gustav Mosander
 Biography: Johan Gadolin
 Biography: Johann Schroder
 Biography: Karl Wilhelm Scheele
 Biography: Martin Heinrich Klaproth
 Biography: Robert Wilhelm Bunsen
 Biography: Sir Humphry Davy
 Biography: William Gregor
 Compounds: Barium
 Compounds: Beryllium
 Compounds: Bismuth
 Compounds: Calcium
 Compounds: Cerium
 Compounds: Chromium
 Compounds: Cobalt
 Compounds: Copper
 Compounds: Dysprosium
 Compounds: Erbium
 Compounds: Fluorine
 Compounds: Hafnium
 Compounds: Holmium
 Compounds: Indium
 Compounds: Iron
 Compounds: Lead
 Compounds: Magnesium
 Compounds: Manganese
 Compounds: Nitrogen
 Compounds: Promethium
 Compounds: Strontium
 Compounds: Sulfur
 Compounds: Thallium
 Compounds: Tin
 Compounds: Vanadium
 Compounds: Ytterbium
 Compounds: Yttrium
 Compounds: Zirconium
 Country: China
 Country: Outer space
 Country: Russia
 Country: Ukraine
 Data1: Aluminium
 Data1: Arsenic
 Data1: Barium
 Data1: Beryllium
 Data1: Cerium
 Data1: Chromium
 Data1: Cobalt
 Data1: Erbium
 Data1: Europium
 Data1: Gadolinium
 Data1: Holmium
 Data1: Indium
 Data1: Lanthanum
 Data1: Lithium
 Data1: Magnesium
 Data1: Manganese
 Data1: Neodymium
 Data1: Osmium
 Data1: Oxygen
 Data1: Protactinium
 Data1: Rhodium
 Data1: Ruthenium
 Data1: Samarium
 Data1: Scandium
 Data1: Terbium
 Data1: Thallium
 Data1: Thulium
 Data1: Titanium
 Data1: Uranium
 Data1: Vanadium
 Data1: Yttrium
 Data1: Zinc
 Data1: Zirconium
 Glossary: Magnetic Ordering
 Glossary: Rare Earth Elements
 On This Day... 11 December
 On This Day... 14 December
 On This Day... 16 April
 Production: Aluminium
 Production: Arsenic
 Production: Boron
 Production: Cadmium
 Production: Copper
 Production: Iron
 Production: Magnesium
 Production: Nickel
 Production: Rubidium
 Production: Samarium
 Production: Strontium
 Production: Tantalum
 Production: Terbium
 Production: Thorium
 Production: Thulium
 Production: Tungsten
 Production: Zinc
 Production: Zirconium
 Reactions: Actinium
 Reactions: Aluminium
 Reactions: Barium
 Reactions: Beryllium
 Reactions: Boron
 Reactions: Bromine
 Reactions: Cadmium
 Reactions: Calcium
 Reactions: Carbon
 Reactions: Cerium
 Reactions: Cobalt
 Reactions: Dysprosium
 Reactions: Erbium
 Reactions: Europium
 Reactions: Gadolinium
 Reactions: Germanium
 Reactions: Hafnium
 Reactions: Holmium
 Reactions: Iridium
 Reactions: Iron
 Reactions: Lanthanum
 Reactions: Lead
 Reactions: Lithium
 Reactions: Lutetium
 Reactions: Magnesium
 Reactions: Manganese
 Reactions: Mercury
 Reactions: Neodymium
 Reactions: Nickel
 Reactions: Niobium
 Reactions: Osmium
 Reactions: Palladium
 Reactions: Praseodymium
 Reactions: Radium
 Reactions: Rhenium
 Reactions: Rhodium
 Reactions: Ruthenium
 Reactions: Samarium
 Reactions: Scandium
 Reactions: Selenium
 Reactions: Silicon
 Reactions: Sodium
 Reactions: Strontium
 Reactions: Tantalum
 Reactions: Technetium
 Reactions: Tellurium
 Reactions: Terbium
 Reactions: Thallium
 Reactions: Thulium
 Reactions: Titanium
 Reactions: Tungsten
 Reactions: Uranium
 Reactions: Vanadium
 Reactions: Yttrium
 Reactions: Zinc
 Reactions: Zirconium
 
oxides (134)
 Biography: Louis Jacques Thenard
 Biography: Sir Humphry Davy
 Compounds: Chlorine
 Compounds: Fluorine
 Compounds: Hafnium
 Compounds: Nitrogen
 Compounds: Plutonium
 Compounds: Tin
 Country: Brazil
 Country: Canada
 Country: Chile
 Country: India
 Country: Malaysia
 Data1: Antimony
 Data1: Arsenic
 Data1: Cerium
 Data1: Copper
 Data1: Iron
 Data1: Thorium
 Data1: Thulium
 Data1: Titanium
 Data1: Yttrium
 Data1: Zinc
 Data2: Actinium
 Data2: Aluminium
 Data2: Americium
 Data2: Antimony
 Data2: Arsenic
 Data2: Astatine
 Data2: Barium
 Data2: Berkelium
 Data2: Beryllium
 Data2: Bismuth
 Data2: Boron
 Data2: Bromine
 Data2: Cadmium
 Data2: Caesium
 Data2: Calcium
 Data2: Californium
 Data2: Carbon
 Data2: Cerium
 Data2: Chlorine
 Data2: Chromium
 Data2: Cobalt
 Data2: Copper
 Data2: Curium
 Data2: Dysprosium
 Data2: Erbium
 Data2: Europium
 Data2: Fluorine
 Data2: Francium
 Data2: Gadolinium
 Data2: Gallium
 Data2: Germanium
 Data2: Gold
 Data2: Hafnium
 Data2: Holmium
 Data2: Hydrogen
 Data2: Indium
 Data2: Iodine
 Data2: Iron
 Data2: Lanthanum
 Data2: Lawrencium
 Data2: Lead
 Data2: Lithium
 Data2: Lutetium
 Data2: Magnesium
 Data2: Manganese
 Data2: Mercury
 Data2: Molybdenum
 Data2: Neodymium
 Data2: Neptunium
 Data2: Nickel
 Data2: Niobium
 Data2: Nitrogen
 Data2: Nobelium
 Data2: Osmium
 Data2: Oxygen
 Data2: Palladium
 Data2: Phosphorus
 Data2: Platinum
 Data2: Plutonium
 Data2: Polonium
 Data2: Potassium
 Data2: Praseodymium
 Data2: Promethium
 Data2: Protactinium
 Data2: Radium
 Data2: Rhenium
 Data2: Rhodium
 Data2: Rubidium
 Data2: Ruthenium
 Data2: Samarium
 Data2: Scandium
 Data2: Selenium
 Data2: Silicon
 Data2: Silver
 Data2: Sodium
 Data2: Sulfur
 Data2: Tantalum
 Data2: Technetium
 Data2: Tellurium
 Data2: Terbium
 Data2: Thallium
 Data2: Thorium
 Data2: Thulium
 Data2: Tin
 Data2: Titanium
 Data2: Tungsten
 Data2: Uranium
 Data2: Vanadium
 Data2: Xenon
 Data2: Ytterbium
 Data2: Yttrium
 Data2: Zinc
 Data2: Zirconium
 Document: The Alkaline Earth Metals (Group 2)
 Glossary: Magnetic Ordering
 Glossary: Metals
 Glossary: Rare Earth Elements
 Glossary: Refractory
 Production: Arsenic
 Production: Iron
 Production: Oxygen
 Production: Rubidium
 Production: Uranium
 Production: Yttrium
 Production: Zinc
 Reactions: Iron
 Reactions: Lead
 Reactions: Mercury
 Reactions: Neptunium
 Reactions: Plutonium
 Reactions: Uranium
 
oxiding (1)
 Glossary: Allotrope
 
oxidisation (1)
 Data1: Argon
 
oxidise (1)
 Production: Zinc
 
oxidised (2)
 Production: Aluminium
 Production: Arsenic
 
oxidises (1)
 Data1: Lanthanum
 
oxidising (1)
 Compounds: Vanadium
 
oxidizable (2)
 Data2: Bromine
 Data2: Oxygen
 
oxidize (7)
 Allotrope: Arsenic
 Compounds: Chromium
 Data1: Erbium
 Data1: Rhenium
 Document: The Alkali (Group 1) Metals
 Production: Hydrogen
 Reactions: Beryllium
 
oxidized (2)
 Data1: Cobalt
 Production: Barium
 
oxidizer (10)
 Allotrope: Oxygen
 Compounds: Chlorine
 Compounds: Lithium
 Compounds: Nitrogen
 Compounds: Potassium
 Compounds: Strontium
 Data1: Manganese
 Data2: Chlorine
 Data2: Fluorine
 Data2: Oxygen
 
oxidizers (23)
 Data1: Nitrogen
 Data2: Aluminium
 Data2: Antimony
 Data2: Beryllium
 Data2: Cadmium
 Data2: Calcium
 Data2: Carbon
 Data2: Chromium
 Data2: Cobalt
 Data2: Copper
 Data2: Fluorine
 Data2: Hafnium
 Data2: Lead
 Data2: Manganese
 Data2: Molybdenum
 Data2: Phosphorus
 Data2: Selenium
 Data2: Silicon
 Data2: Tantalum
 Data2: Tellurium
 Data2: Vanadium
 Data2: Yttrium
 Data2: Zirconium
 
oxidizes (4)
 Data1: Europium
 Reactions: Arsenic
 Reactions: Boron
 Reactions: Iron
 
oxidizing (19)
 Allotrope: Oxygen
 Compounds: Lithium
 Data1: Antimony
 Data1: Bromine
 Data1: Copper
 Data1: Lithium
 Data1: Nitrogen
 Data2: Hydrogen
 Data2: Lithium
 On This Day... 25 June
 Reactions: Iron
 Reactions: Mercury
 Reactions: Phosphorus
 Reactions: Rhenium
 Reactions: Selenium
 Reactions: Sulfur
 Reactions: Technetium
 Reactions: Tellurium
 Reactions: Zinc
 
oxigenio (1)
 Names: Oxygen
 
oxigeno (1)
 Names: Oxygen
 
oximes (1)
 On This Day... 22 July
 
oxoacid (1)
 Compounds: Krypton
 
oxoacids (1)
 Production: Oxygen
 
oxus (1)
 Data1: Oxygen
 
oxychloride (1)
 On This Day... 26 November
 
oxygen (121)
 Allotrope: Carbon
 Allotrope: Oxygen
 Atomic data: Oxygen
 Biography: Antoine-Laurent de Lavoisier
 Biography: Daniel Rutherford
 Biography: Henry Cavendish
 Biography: John Dalton
 Biography: Joseph Priestley
 Biography: Karl Wilhelm Scheele
 Biography: Louis Jacques Thenard
 Biography: Philip Hauge Abelson
 Biography: Pierre Jules César Janssen
 Compounds: Boron
 Compounds: Carbon
 Compounds: Chlorine
 Compounds: Hydrogen
 Compounds: Iron
 Compounds: Lithium
 Compounds: Magnesium
 Compounds: Nitrogen
 Compounds: Oxygen
 Compounds: Plutonium
 Compounds: Potassium
 Compounds: Sodium
 Compounds: Sulfur
 Compounds: Vanadium
 Compounds: Zirconium
 Country: Outer space
 Country: United States of America
 Data1: Argon
 Data1: Carbon
 Data1: Chlorine
 Data1: Cobalt
 Data1: Gadolinium
 Data1: Helium
 Data1: Hydrogen
 Data1: Iodine
 Data1: Iron
 Data1: Neon
 Data1: Nitrogen
 Data1: Oxygen
 Data1: Phosphorus
 Data1: Rhodium
 Data1: Silicon
 Data1: Sodium
 Data1: Tin
 Data1: Titanium
 Data2: Calcium
 Data2: Oxygen
 Data2: Rhodium
 Document: Abundance of the Elements in the Solar System
 Document: Chemical makeup of the human body
 Document: The Alkali (Group 1) Metals
 Glossary: Air
 Glossary: Allotrope
 Glossary: Doubly Magic
 Glossary: Endothermic
 Glossary: Mole
 Glossary: Molecule
 Glossary: Positron Emission (Beta+ Decay)
 Glossary: Refractory
 Isotope: Beryllium
 Isotope: Oxygen
 MAC data: Oxygen
 Names: Oxygen
 On This Day... 16 December
 On This Day... 19 April
 On This Day... 21 September
 On This Day... 26 April
 On This Day... 28 October
 On This Day... 29 January
 On This Day... 4 May
 Production: Aluminium
 Production: Argon
 Production: Cadmium
 Production: Carbon
 Production: Hydrogen
 Production: Iron
 Production: Neon
 Production: Oxygen
 Production: Phosphorus
 Production: Silicon
 Production: Tellurium
 Reactions: Aluminium
 Reactions: Antimony
 Reactions: Arsenic
 Reactions: Bismuth
 Reactions: Bromine
 Reactions: Caesium
 Reactions: Carbon
 Reactions: Chlorine
 Reactions: Chromium
 Reactions: Copper
 Reactions: Fluorine
 Reactions: Germanium
 Reactions: Hydrogen
 Reactions: Iodine
 Reactions: Iridium
 Reactions: Iron
 Reactions: Lead
 Reactions: Manganese
 Reactions: Molybdenum
 Reactions: Neptunium
 Reactions: Nickel
 Reactions: Osmium
 Reactions: Oxygen
 Reactions: Palladium
 Reactions: Platinum
 Reactions: Plutonium
 Reactions: Potassium
 Reactions: Rhenium
 Reactions: Rhodium
 Reactions: Rubidium
 Reactions: Ruthenium
 Reactions: Silicon
 Reactions: Technetium
 Reactions: Thorium
 Reactions: Tin
 Reactions: Tungsten
 Reactions: Vanadium
 Spectrum: Oxygen
 
oxygene (1)
 Names: Oxygen
 
oxygenic (1)
 Production: Oxygen
 
oxygenium (1)
 Names: Oxygen
 
oxyhalides (1)
 Compounds: Plutonium
 
oxypentafluoroniobate (1)
 Data1: Tantalum
 
oxysulfide (1)
 Data1: Sulfur
 
oz (3)
 Data1: Astatine
 Production: Astatine
 Production: Rhodium
 
ozein (1)
 Allotrope: Oxygen
 
ozonated (1)
 Compounds: Oxygen
 
ozone (13)
 Allotrope: Oxygen
 Compounds: Chlorine
 Compounds: Oxygen
 Data1: Fluorine
 Data1: Oxygen
 Glossary: Allotrope
 On This Day... 18 October
 On This Day... 28 June
 On This Day... 3 December
 Reactions: Bromine
 Reactions: Fluorine
 Reactions: Iodine
 Reactions: Oxygen
 
ozote (1)
 Data1: Nitrogen