Science / Chemistry / Hydrogen: Element 1, atomic weight 1.00797. The most abundant element in the universe. Hydrogen occurs as H2 at ambient temperature and pressure, a colorless, odorless, and extremely flammable gas. Discovered in 1766 by Cavendish.

Hydrogen (H)

Science / Periodic Table of Elements / Hydrogen (H): Atomic number: 1, Atomic mass: 1.007825 g.mol -1, Electronegativity: 2.1, Density: 0.0899*10 -3 g.cm -3 at 20 °C, Melting point: - 259.2 °C, Boiling point: - 252.8 °C, Vanderwaals radius: 0.12 nm, MORE

Standard Hydrogen Electrode

Science / Chemistry / Standard Hydrogen Electrode: A platinum electrode that runs the half reaction 2 H+(aq, 1M) + 2 e- rightarrow H2(g, 1 atm), chosen as a reference for cell voltages. The electrode potential of the standard hydrogen electrode is def MORE

Hydrogen Bond

Science / Biology / Hydrogen Bond: A weak bond between two atoms (one of which is hydrogen) with partial but opposite electrical charges. MORE

Hydrogen Peroxide

Entertainment / Photography / Hydrogen Peroxide: Chemical used in hypo clearing agents. MORE


Health / Dentistry / Bleaching: The technique of applying a chemical agent, usually hydrogen peroxide, to the teeth to whiten them. MORE


Business / Agriculture / Ph: An expression of the intensity of the basic or acidic condition of a liquid or of soil: the logarithmic scale ranges from 0 to 14, where 0 is the most acid, 7 is neutral, and above 7 is alkaline. Natu MORE