hydrogen: Quick Facts

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Nov. 13, 2026

News •

Scientists May Have Discovered a Massive Starless Galaxy • Nov. 9, 2026, 6:15 AM ET (WIRED)

What ended the 'Cosmic Dark Age'? Astronomers say they're closer than ever to an answer. • Oct. 31, 2026, 11:00 AM ET (Live Science)

FAST and Arecibo point to possible dark galaxy with vast hydrogen reservoir • Oct. 26, 2026, 6:55 AM ET (Phys.org)

Curated hydrogen database reveals links between storage capacity and release pressure • Oct. 23, 2026, 10:20 AM ET (Tech Xplore)

Facts

Also Known As	H

Photos and Videos

Diagram highlighting hydrogen's chemical properties, showing its atomic number (1), symbol (H), electron configuration (1s1), atomic weight, crystal structure, physical state as a gas at room temperature, and classification as a nonmetal.

Balmer series of hydrogen

explosion limits

Line graph showing the first ionization energies of the elements as a function of atomic number, with peaks at noble gases like helium, neon, argon, krypton, xenon, and radon, and labeled elements at key points.

Diagram comparing the hydrogen atom's energy levels using Bohr's model, the Schrodinger equation, and the Dirac equation, with horizontal lines representing quantized binding energies and labels for each energy state.

Figure 15: Transformations of hydrogen compounds in the atmosphere.

Diagram showing electron density shapes for atomic orbitals: A spherical s orbital at the top left, and three dumbbell-shaped p orbitals oriented along the x, y, and z axes below, each with labeled axes.

electron density functions for four hydrogen atom states

Figure 9: Oxidation path for methane, CH4.

Diagram showing the formation of a polar covalent bond in a water molecule, with two hydrogen atoms bonding to one oxygen atom to form H2O, illustrating shared electrons and chemical reaction.

Learn about new water molecule-splitting technology that separates hydrogen and oxygen

Understanding acids, bases, and the pH scale

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Topics

hydride deuterium tritium protium Lyman series Balmer series Paschen series Pfund series Brackett series nitric acid rare-earth element transition metal alkali metal actinoid element carbon sodium nitrogen alkaline-earth metal sulfur carbon group element

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Key People

Henry Cavendish

Henry Cavendish

British physicist

Portrait of French chemist Antoine Laurent Lavoisier, shown in formal 18th-century attire with a white wig and ruffled cravat, looking slightly to his left.

Antoine Lavoisier

French chemist

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Otto Struve

American astronomer

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Anders Jonas Ångström

Swedish physicist

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Fritz Wolfgang London

American physicist

Periodic Table of the elements concept image (chemistry)

Facts You Should Know: The Periodic Table Quiz

Concept artwork on the periodic table of elements.

118 Names and Symbols of the Periodic Table Quiz

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