hydrogel
— Noun
– English
～ a colloidal gel in which water is the dispersion medium
hydrogen-bomb
— Verb
– English
～ attack with a hydrogen bomb
heavy hydrogen
— Noun
– English
～ an isotope of hydrogen which has one neutron (as opposed to zero neutrons in hydrogen)
hydrogen bromide
— Noun
– English
～ a colorless gas that yields hydrobromic acid in solution with water
hydrogen azide
— Noun
– English
～ a colorless explosive liquid that is volatile and poisonous and foul-smelling
hydrogen chloride
— Noun
– English
～ a colorless corrosive gas (HCl)
hydrogen
— Noun
– English
～ a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
hydrogen fluoride
— Noun
– English
～ a colorless poisonous corrosive liquid made by the action of sulphuric acid on calcium fluoride; solutions in water are hydrofluoric acid
hydrogen bond
— Noun
– English
～ a chemical bond consisting of a hydrogen atom between two electronegative atoms (e.g., oxygen or nitrogen) with one side be a covalent bond and the other being an ionic bond
hydrogen cyanide
— Noun
– English
～ a highly poisonous gas or volatile liquid that smells like bitter almonds; becomes a gas at around 90 degree Fahrenheit and is most dangerous when inhaled; the anhydride of hydrocyanic acid; used in manufacturing
hydrogen bomb
— Noun
– English
～ a nuclear weapon that releases atomic energy by union of light (hydrogen) nuclei at high temperatures to form helium
hydrogen carbonate
— Noun
– English
～ a salt of carbonic acid (containing the anion HCO3) in which one hydrogen atom has been replaced; an acid carbonate
hydrogen atom
— Noun
– English
～ an atom of hydrogen
hydrogenate
— Verb
– English
～ combine or treat with or expose to hydrogen; add hydrogen to the molecule of (an unsaturated organic compound)
hydrogenation
— Noun
– English
～ a chemical process that adds hydrogen atoms to an unsaturated oil; "food producers use hydrogenation to keep fat from becoming rancid"
hydrographic
— Adjective
– English
～ of or relating to the science of hydrography
hydrographical
— Adjective
– English
～ of or relating to the science of hydrography
hydrography
— Noun
– English
～ the science of the measurement and description and mapping of the surface waters of the earth with special reference to navigation
hydroid
— Noun
– English
～ colonial coelenterates having the polyp phase dominant
hydroiodic acid
— Noun
– English
～ an acid formed by aqueous solution of hydrogen iodide