| 释义 |
WordReference Random House Learner's Dictionary of American English © 2024hy•dro•gen /ˈhaɪdrədʒən/USA pronunciation n. [uncountable]- Chemistrya colorless, odorless gas that burns easily, and combines chemically with oxygen to form water.
See -hydr-. WordReference Random House Unabridged Dictionary of American English © 2024hy•dro•gen (hī′drə jən),USA pronunciation n. - Chemistrya colorless, odorless, flammable gas that combines chemically with oxygen to form water: the lightest of the known elements. Symbol: H;
at. wt.: 1.00797;
at. no.: 1;
density: 0.0899 g/l at 0°C and 760 mm pressure.
- French hydrogène. See hydro-1, -gen
- 1785–95
Collins Concise English Dictionary © HarperCollins Publishers:: hydrogen /ˈhaɪdrɪdʒən/ n - a flammable colourless gas that is the lightest and most abundant element in the universe. It occurs mainly in water and in most organic compounds and is used in the production of ammonia and other chemicals, in the hydrogenation of fats and oils, and in welding. Symbol: H; atomic no: 1; atomic wt: 1.00794; valency: 1; density: 0.08988 kg/m³; melting pt: –259.34°C; boiling pt: –252.87°C
- (as modifier): hydrogen bomb
Etymology: 18th Century: from French hydrogène, from hydro- + -gen; so called because its combustion produces water |