In dictionaries:
atomic number 1
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
atomic number 2
a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
atomic number 3
a soft silver-white univalent element of the alkali metal group; the lightest metal known; occurs in several minerals
atomic number 4
a light strong brittle gray toxic bivalent metallic element
atomic number 6
an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds
atomic number 7
a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
atomic number 8
a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
atomic number 10
a colorless odorless gaseous element that give a red glow in a vacuum tube; one of the six inert gasses; occurs in the air in small amounts
atomic number 100
a radioactive transuranic metallic element produced by bombarding plutonium with neutrons
atomic number 101
a radioactive transuranic element synthesized by bombarding einsteinium with alpha particles (Md is the current symbol for mendelevium but Mv was formerly the symbol)
atomic number 102
a radioactive transuranic element synthesized by bombarding curium with carbon ions; 7 isotopes are known
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