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  1. Hydrogen - Wikipedia

    Under standard conditions, hydrogen is a gas of diatomic molecules with the formula H2, called dihydrogen, or sometimes hydrogen gas, molecular hydrogen, or simply hydrogen. Dihydrogen is …

  2. H2 properties - Chemical Portal

    Liquid hydrogen (H₂ (l)) represents the cryogenic liquid state of molecular hydrogen, existing below its critical temperature of 33.0 K. This cryogenic fluid exhibits a boiling point of 20.28 K at standard …

  3. What is h2 in chemistry? - California Learning Resource Network

    Apr 18, 2025 · Hydrogen (H 2), a diatomic molecule consisting of two hydrogen atoms covalently bonded, holds a position of paramount importance in chemistry, physics, and increasingly, in …

  4. Hydrogen - Reactivity, Uses, Properties | Britannica

    Dec 7, 2025 · One molecule of hydrogen dissociates into two atoms (H 2 → 2H) when an energy equal to or greater than the dissociation energy (i.e., the amount of energy required to break the bond that …

  5. The global hydrogen budget - Nature

    Dec 13, 2025 · Trends in global H2 sources and sinks are analysed from 1990 to 2020, and a comprehensive budget for the decade 2010–2020 is presented.

  6. Hydrogen (H) - Definition, Preparation, Properties, Uses, Compounds ...

    Jan 21, 2025 · We write H2 instead of H because hydrogen naturally exists as a diatomic molecule, meaning two hydrogen atoms bond together to form H2, the most stable form of hydrogen gas.

  7. 3.2: Hydrogen - The Simplest Atom - Chemistry LibreTexts

    This page discusses hydrogen (H), the first element, primarily as the diatomic molecule (H2), a colorless, odorless gas used in industries like ammonia and methanol production.

  8. H2 Definition - General Biology I Key Term | Fiveable

    H2 is the most abundant molecule in the universe, playing a crucial role in the formation of stars and galaxies. In biological systems, H2 is produced during metabolic processes and serves as an …

  9. Hydrogen - Formula, Properties, Uses, Facts - Study Chemistry

    Hydrogen, symbol H, molecular formula H2 is a colourless, odourless, tasteless, flammable gaseous chemical substances among the periodic table family

  10. Hydrogen - NIST Chemistry WebBook

    NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of …