Name: Hydrogen Symbol:H
Atomic Number: 1 Atomic Weight: 1.01
Discovery:1766; by Cavendish in London, England
Note: colorless gas, less dense than air, very flammable
Name: Helium Symbol: He
Atomic Number: 2 Atomic Weight: 4.00
Discovery: 1895; by Ramsay in London, England
Note: colorless gas, less dense than air, non- flammable; used in blimps
Name: Lithium Symbol: Li
Atomic Number: 3 Atomic Weight: 6.94
Discovery: 1817; Arfvedson; Stockholm, Sweden
Note: soft metal, reacts slowly with oxygen and water; used in medicine, batteries, and grease products
Name: Beryllium Symbol: Be
Atomic Number: 4 Atomic Weight: 9.01
Discovery: 1797; by Vauquelin in Paris, France
Note: soft, shiny metal; does not react with water or air; used with copper to make spark proof tools
Name: Boron Symbol: B
Atomic Number: 5 Atomic Weight: 10.81
Discovery: 1808; by Lussac and Davy in London
Note: non-metal; unreactive with water or oxygen; used in detergents, glass making, and fire proof materials
Name: Carbon Symbol: C
Atomic Number: 6 Atomic Weight: 12.01
Discovery: prehistory; by unknown discoverer
Note: non-metal; conducts electric current; found in coal and other hydrocarbons; used in making steel
Name: Nitrogen Symbol: N
Atomic Number: 7 Atomic Weight: 14.00
Discovery: 1772; Rutherford; Edinburgh, Scotland
Note: colorless gas; breathable air is 78% nitrogen; used in plastics and fertilizers
Name: Oxygen Symbol: O
Atomic Number: 8 Atomic Weight: 15.99
Discovery: 1774; Priestly & Scheele; Leeds, France
Note: colorless gas; very reactive with most elements; used in the chemical industry; breathable air is 21% oxygen
Name: Fluorine Symbol: F
Atomic Number: 9 Atomic Weight: 18.99
Discovery: 1886; by Moissan in Paris, France
Note: yellow gas; found in many organic compounds and salts; the most reactive of all chemical elements; used to make plastics and in aluminum production
Name: Neon Symbol: Ne
Atomic Number: 10 Atomic Weight: 20.18
Discovery: 1898; Travers & Ramsay; London
Note: colorless gas; under normal conditions, will not react with any other elements; used in electric signs
Name: Sodium Symbol: Na
Atomic Number: 11 Atomic Weight: 22.99
Discovery: 1897; by Davy in London, England
Note: soft, very reactive metal; reacts rapidly with water; found in many salts; used by chemists to manufacture many chemicals
Name: Magnesium Symbol: Mg
Atomic Number: 12 Atomic Weight: 24.30
Discovery: 1755; by Black in Edinburgh, Scotland
Note: soft, shiny metal; burns in air; used with other metals to make light weight items
Name: Aluminum Symbol: Al
Atomic Number: 13 Atomic Weight: 26.98
Discovery: 1825; Oersted; Copenhagen, Denmark
Note: hard metal; reacts very rapidly with oxygen to form protective oxide coating; used to manufacture many useful items
Name: Silicon Symbol: Si
Atomic Number: 14 Atomic Weight: 28.09
Discovery: 1824; Berzelius; Stockholm, Sweden
Note: non-metal; common sand is mostly an oxide of silicon, SiO2; used in electronics industry in semiconductors
Name: Phosphorus Symbol: P
Atomic Number: 15 Atomic Weight: 30.97
Discovery: 1669; by Brandt in Hamburg, Germany
Note: soft, non-metal; certain forms are very flammable; used in fertilizers and detergents
Name: Sulfur Symbol: S
Atomic Number: 16 Atomic Weight: 32.07
Discovery: prehistory; discoverer unknown
Note: non-metal solid; burns in air; used in many industrial processes; sulfur oxides in the atmosphere create acid rain
Name: Chlorine Symbol: Cl
Atomic Number: 17 Atomic Weight: 35.45
Discovery: 1774; by Scheele in Uppsala, Sweden
Note: sharp smelling, yellow-green gas; used to make bleach and plastics; made by decomposition of table salt, sodium chloride
Name: Argon Symbol: Ar
Atomic Number: 18 Atomic Weight: 39.95
Discovery: 1894; Ramsay & Rayleigh; London
Note: colorless gas; non-reactive with most other elements; used in light bulbs; 1% of breathable air is argon
Name: Potassium Symbol: K
Atomic Number: 19 Atomic Weight: 39.10
Discovery: 1807; by Davy in London, England
Note: very soft metal; reacts rapidly with water; used in fertilizers and glass
Name: Calcium Symbol: Ca
Atomic Number: 20 Atomic Weight: 40.08
Discovery: 1808; by Davy in London, England
Note: soft metal; calcium oxide is often called powdered lime; calcium gives strength to bone cells
Name: Scandium Symbol: Sc
Atomic Number: 21 Atomic Weight: 44.96
Discovery: 1870; by Nilson in Uppsala, Sweden
Note: soft metal; reacts easily with oxygen; burns in air; scandium is rarely used for anything
Name: Titanium Symbol: Ti
Atomic Number: 22 Atomic Weight: 47.88
Discovery: 1791; by Gregor in Cornwall, England
Note: very hard metal; reacts rapidly with oxygen to form protective oxide layer; titanium oxide is very white and used to make paint; titanium is very strong and is used to make many manufactured items
Name: Vanadium Symbol: V
Atomic Number: 23 Atomic Weight: 50.94
Discovery: 1801; by delRio in Mexico
Note: soft metal; mixed with iron to make corrosion resistant steel
Name: Chromium Symbol: Cr
Atomic Number: 24 Atomic Weight: 51.99
Discovery: 1780; by Vauquelin in Paris, France
Note: very hard blue-white metal; does not readily react with oxygen; used as plating to protect other metals
Name: Manganese Symbol: Mn
Atomic Number: 25 Atomic Weight: 54.94
Discovery: 1774; by Grahn in Stockholm, Sweden
Note: hard, brittle metal; burns in air; used in fertilizers, glass and ceramics, and as an additive in steel making
Name: Iron Symbol: Fe
Atomic Number: 26 Atomic Weight: 55.85
Discovery: 2500 BC; discoverer unknown
Note: soft, shiny metal; combines easily with oxygen to form oxides (rust); one of the most important metals; mixed with carbon to make steel
Name: Cobalt Symbol: Co
Atomic Number: 27 Atomic Weight: 58.93
Discovery: 1735; by Brandt in Stockholm, Sweden
Note: shiny, hard metal; does not readily oxidize; used to make magnets, glass and ceramics, and paint
Name: Nickel Symbol: Ni
Atomic Number: 28 Atomic Weight: 58.69
Discovery: 1751; Cronstedt; Stockholm, Sweden
Note: soft, shiny metal; does not readily oxidize; can be easily formed into shapes; used in coins, metal plating
Name: Copper Symbol: Cu
Atomic Number: 29 Atomic Weight: 63.55
Discovery: 5000 BC; discoverer unknown
Note: soft, red-brown metal; good conductor of electricity; used in coins and electric wires
Name: Zinc Symbol: Zn
Atomic Number: 30 Atomic Weight: 65.39
Discovery: 1500 BC; discoverer unknown
Note: brittle, blue-white metal; oxidizes very rapidly to form protective layer; used in batteries, brass, and for plating (galvanizing) over iron
Name: Gallium Symbol: Ga
Atomic Number: 31 Atomic Weight: 69.72
Discovery: 1875; de Boisbaudran in Paris, France
Note: soft, silvery metal; melts at low temperature, 30 C; semiconductor of electric current; used in electronics
Name: Germanium Symbol: Ge
Atomic Number: 32 Atomic Weight: 72.61
Discovery: 1886; by Winkler in Freiberg, Germany
Note: a semiconductor like silicon; used in high temperature applications where cost is not so important
Name: Arsenic Symbol: As
Atomic Number: 33 Atomic Weight: 74.92
Discovery: 1250; by Magnus in Germany
Note: metalloid; reacts easily with oxygen; burns in air; a poison used in insecticides; used as a wood preservative and in glass making
Name: Selenium Symbol: Se
Atomic Number: 34 Atomic Weight: 78.96
Discovery: 1817; Berzelius; Stockholm, Sweden
Note: very soft, shiny metal; burns in air; does not react with water; used in photoelectric cells and photocopiers
Name: Bromine Symbol: Br
Atomic Number: 35 Atomic Weight: 79.90
Discovery: 1826; by Balard in Montpellier, France
Note: dark red, sharp smelling liquid; used in fire proofing materials and in photographic chemicals; one of the few chemical elements that are liquid at room temperature
Name: Krypton Symbol: Kr
Atomic Number: 36 Atomic Weight: 83.80
Discovery: 1898; Ramsay & Travers; London
Note: colorless gas; under normal conditions, does not react with other chemical elements, very rare
Name: Rubidium Symbol: Rb
Atomic Number: 37 Atomic Weight: 85.47
Discovery: 1861; Bunsen & Kirchoff; Germany
Note: very soft, shiny metal; ignites in air and explodes in water; Rubidium is rarely used
Name: Strontium Symbol: Sr
Atomic Number: 38 Atomic Weight: 87.62
Discovery: 1808; Crawford; Edinburgh, Scotland
Note: soft, shiny metal; burns in air; burns with a bright red color; used in fireworks and flares
Name: Yttrium Symbol: Y
Atomic Number: 39 Atomic Weight: 88.91
Discovery: 1794; by Gadolin in Finland
Note: soft, shiny metal; burns very easily; reacts with water; used in manufacture of television screens; gives red color to television images
Name: Zirconium Symbol: Zr
Atomic Number: 40 Atomic Weight: 91.22
Discovery: 1789; by Klaproth in Berlin, Germany
Note: hard, shiny metal; burns in air; used to make bricks, ceramics, and abrasives
Name: Niobium Symbol: Nb
Atomic Number: 41 Atomic Weight: 92.91
Discovery: 1801; by Hatchett in London, England
Note: soft, shiny metal; resists corrosion, used with iron to make stainless steel
Name: Molybdenum Symbol: Mo
Atomic Number: 42 Atomic Weight: 95.94
Discovery: 1781; by Hjelm in Uppsala, Sweden
Note: soft, shiny metal; usually found as a gray powder; used to strengthen steel
Name: Technetium Symbol: Tc
Atomic Number: 43 Atomic Weight: 98
Discovery: 1937; Perrier & Segre; Palermo, Italy
Note: shiny metal; radioactive; does not occur naturally and must be produced in nuclear reactors
Name: Ruthenium Symbol: Ru
Atomic Number: 44 Atomic Weight: 101.07
Discovery: 1808; by Sniadecki in Poland
Note: very shiny metal; does not react with oxygen; used in jewelry to strengthen platinum
Name: Rhodium Symbol: Rh
Atomic Number: 45 Atomic Weight: 102.91
Discovery: 1803; by Wollaston in London, England
Note: very rare element; hard, shiny metal; used in chemical laboratories
Name: Palladium Symbol: Pd
Atomic Number: 46 Atomic Weight: 106.42
Discovery: 1803; by Wollaston in London, England
Note: shiny metal; radioactive; usually found with uranium; rarely used
Name: Silver Symbol: Ag
Atomic Number: 47 Atomic Weight: 107.87
Discovery: 3000 BC; discoverer unknown
Note: soft, shiny metal; noble metal; used in photographic chemicals; jewelry, coins; good electrical conductor
Name: Cadmium Symbol: Cd
Atomic Number: 48 Atomic Weight: 112.41
Discovery: 1817; by Davy in London, England
Note: shiny metal; oxidizes easily; used in paint and rechargeable batteries
Name: Indium Symbol: In
Atomic Number: 49 Atomic Weight: 114.82
Discovery: 1863; by Reich in Freiberg, Germany
Note: soft metal; has a low melting point, (157 C); used to make low melting metals and to make transistors
Name: Tin Symbol: Sn
Atomic Number: 50 Atomic Weight: 118.71
Discovery: 2100 BC; discoverer unknown
Note: very soft metal; forms protective oxide layer; used in metal plating and solder
Name: Antimony Symbol: Sb
Atomic Number: 51 Atomic Weight: 121.76
Discovery: 1600 BC; discoverer unknown
Note: metalloid; shiny and brittle; used in storage batteries and as an additive to harden other metals
Name: Tellurium Symbol: Te
Atomic Number: 52 Atomic Weight: 127.60
Discovery: 1783; by von Reichenstein in Romania
Note: shiny white metal; burns in air; used in electronics and as an additive to metals to make them easier to form
Name: Iodine Symbol: I
Atomic Number: 53 Atomic Weight: 126.91
Discovery: 1811; by Courtois in Paris, France
Note: black, shiny non-metal solid; changes state from solid to gas (sublimes) at room temperature; used in dyes and disinfectants
Name: Xenon Symbol: Xe
Atomic Number: 54 Atomic Weight: 131.29
Discovery: 1898; Ramsay & Travers; London
Note: colorless gas; under normal conditions, does not react with other elements; used in light bulbs and research laboratories
Name: Cesium Symbol: Cs
Atomic Number: 55 Atomic Weight: 132.91
Discovery: 1860; Bunsen & Kirchoff; Germany
Note: soft, gold colored metal; explodes in water; used in special glass and to monitor radioactive materials
Name: Barium Symbol: Ba
Atomic Number: 56 Atomic Weight: 137.33
Discovery: 1808; by Davy in London, England
Note: soft, shiny white metal; used in medicines, paint, glass making
Name: Lanthanum Symbol: La
Atomic Number: 57 Atomic Weight: 138.91
Discovery: 1839; Mosander; Stockholm, Sweden
Note: soft, white metal; burns in air; used to make microscope and telescope lenses; used in medicine
Name: Hafnium Symbol: Hf
Atomic Number: 72 Atomic Weight: 178.49
Discovery: 1923; Coster & Hevesey; Copenhagen
Note: very shiny, soft metal; burns in air; used for control rods in nuclear reactors
Name: Tantalum Symbol: Ta
Atomic Number: 73 Atomic Weight: 180.95
Discovery: 1802; by Ekeberg in Uppsala, Sweden
Note: soft, shiny metal; very corrosion resistant; used in electronics, special tools, and in surgery for body part replacements
Name: Tungsten Symbol: W
Atomic Number: 74 Atomic Weight: 183.85
Discovery: 1783; by Elhuijar in Spain
Note: shiny, white metal; very high melting point, (3390 C); used in light bulb filaments and cutting tools
Name: Rhenium Symbol: Re
Atomic Number: 75 Atomic Weight: 186.21
Discovery: 1925; Noddack in Berlin, Germany
Note: shiny metal; resists corrosion; high melting point; used in electronics
Name: Osmium Symbol: Os
Atomic Number: 76 Atomic Weight: 190.20
Discovery: 1803; Tennant in London, England
Note: very shiny metal; does not react with many chemicals; has acrid odor; used in metal alloys
Name: Iridium Symbol: Ir
Atomic Number: 77 Atomic Weight: 192.22
Discovery: 1803; Tennant in London, England
Note: hard, shiny metal; very stable; does not react with acids; used in spark plugs
Name: Platinum Symbol: Pt
Atomic Number: 78 Atomic Weight: 195.08
Discovery: 1700 BC; discoverer unknown
Note: very shiny metal; unaffected by oxygen and most chemicals; used to make jewelry and drugs
Name: Gold Symbol: Au
Atomic Number: 79 Atomic Weight: 196.97
Discovery: 3000 BC; discoverer unknown
Note: rare, soft, yellow metal; does not react with oxygen; used in jewelry and coins; world's supply of gold would fit in a cube, 40 feet on each side
Name: Mercury Symbol: Hg
Atomic Number: 80 Atomic Weight: 200.59
Discovery: 1500 BC; discoverer unknown
Note: shiny, liquid metal; mercury vapor is poisonous; melting point is -39 C.; used in electronics, lighting; and fungicides
Name: Thallium Symbol: Tl
Atomic Number: 81 Atomic Weight: 204.38
Discovery: 1861; Crookes in London, England
Note: soft, shiny gray metal; very toxic to humans; few uses; used in special glass
Name: Lead Symbol: Pb
Atomic Number: 82 Atomic Weight: 207.20
Discovery: 1000 BC; discoverer unknown
Note: very soft, weak, dull gray metal; used in paint, glass, solder, radiation shielding, and batteries
Name: Bismuth Symbol: Bi
Atomic Number: 83 Atomic Weight: 208.98
Discovery: 1500 BC; discoverer unknown
Note: brittle, shiny pink metal; does not oxidize easily; used in drugs, electronics, and paints
Name: Polonium Symbol: Po
Atomic Number: 84 Atomic Weight: 209
Discovery: 1898; by Curie in Paris, France
Note: shiny, gray metal; radioactive; used as a source of radiation to power space equipment
Name: Astatine Symbol: At
Atomic Number: 85 Atomic Weight: 210
Discovery: 1940; Corson; Berkeley, California
Note: metalloid; soft, gray, and brittle; burns in oxygen; used in glass, insecticides and wood preservatives
Name: Radon Symbol: Rn
Atomic Number: 86 Atomic Weight: 222
Discovery: 1900; by Dorn in Halle, Germany
Note: colorless gas; radioactive; does not react with other chemical elements; very toxic to humans
Name: Francium Symbol: Fr
Atomic Number: 87 Atomic Weight: 223
Discovery: 1939; by Perey in Paris, France
Note: metal; very radioactive; extremely rare; traces can be found in uranium ore
Name: Radium Symbol: Ra
Atomic Number: 88 Atomic Weight: 226.03
Discovery: 1898; Curie & Curie; Paris, France
Note: soft shiny metal; found in uranium ore; rarely used; toxic to humans
Name: Actnium Symbol: Ac
Atomic Number: 89 Atomic Weight: 227
Discovery: 1899; by Debierne in Paris, France
Note: soft, shiny metal; extremely rare; glows in the dark; radioactive; only a trace exists in the earth's crust; can be manufactured in nuclear reactors
Name: Unnilquadium Symbol: Unq
Atomic Number: 104 Atomic Weight: 261
Discovery: 1964; in the Soviet Union
Note: metal; radioactive; does not occur naturally; made by bombarding Californium atoms with carbon nuclei; a few thousand atoms have been produced
Name: Unnilpentium Symbol: Unp
Atomic Number: 105 Atomic Weight: 262
Discovery: 1967; in the Soviet Union
Note: metal; radioactive; does not occur naturally; made by bombarding Californium atoms with nitrogen nuclei; only a few atoms have been produced
Name: Unnilhexium Symbol: Unh
Atomic Number: 106 Atomic Weight: 263
Discovery: 1974; in the Soviet Union
Note: metal; radioactive; does not occur naturally; only a few atoms have been produced
Name: Unnilseptium Symbol: Uns
Atomic Number: 107 Atomic Weight: 262
Discovery: 1976; in the Soviet Union
Note: metal; radioactive; does not occur naturally; only a few atoms have been produced
Name: Unniloctium Symbol: Uno
Atomic Number: 108 Atomic Weight: 265
Discovery: 1984; in West Germany
Note: metal; radioactive; does not occur naturally; only a few atoms have been produced
Name: Unnilennium Symbol: Une
Atomic Number: 109 Atomic Weight: 266
Discovery: 1982; in West Germany
Note: metal; radioactive; does not occur naturally; only a few atoms have been produced
Name: Unununium Symbol: Uun
Atomic Number: 110 Atomic Weight: 268
Discovery: 1987; in the Soviet Union
Note: metal; radioactive; does not occur naturally; only a few atoms have been produced
Name: Cerium Symbol: Ce
Atomic Number: 58 Atomic Weight: 140.12
Discovery: 1803; Berzelius & Hisinger; Sweden
Note: soft gray metal; very reactive with other elements; used to make glass and ceramics
Name: Praseodymium Symbol: Pr
Atomic Number: 59 Atomic Weight: 140.90
Discovery: 1885; von Welsbach; Vienna, Austria
Note: soft, shiny metal; reacts rapidly with water; used to make magnets and as an additive to make glass lenses for welders
Name: Neodymium Symbol: Nd
Atomic Number: 60 Atomic Weight: 144.24
Discovery: 1885; von Welsbach; Vienna, Austria
Note: shiny, white metal; reacts slowly with oxygen; used to make permanent magnets and glass
Name: Promethium Symbol: Pm
Atomic Number: 61 Atomic Weight: 145
Discovery: 1945; by Marinsky in the USA
Note: rare metal; radioactive; used to make super-miniature batteries
Name: Samarium Symbol: Sm
Atomic Number: 62 Atomic Weight: 150.36
Discovery: 1879; de Boisbaudan; Paris, France
Note: shiny, white metal; used to make special glass and ceramics; used in electronics
Name: Europium Symbol: Eu
Atomic Number: 63 Atomic Weight: 151.97
Discovery: 1901; Demarcay in Paris, France
Note: rare metal; very reactive with other elements; very few uses; used to make thin-film superconductors
Name: Gadolinium Symbol: Gd
Atomic Number: 64 Atomic Weight: 157.25
Discovery: 1880; deMarignac; Geneva, Switzerland
Note: shiny, white metal; reacts slowly with air; used to make recording heads for tape recorders and magnets
Name: Terbium Symbol: Tb
Atomic Number: 65 Atomic Weight: 158.93
Discovery: 1843; Mosander; Stockholm, Sweden
Note: shiny, white metal; used to make lasers
Name: Dysprosium Symbol: Dy
Atomic Number: 66 Atomic Weight: 162.50
Discovery: 1886; de Boisbaudan; Paris, France
Note: shiny, hard metal; reacts with water; used in making metal alloys strong and magnets
Name: Holmium Symbol: Ho
Atomic Number: 67 Atomic Weight: 164.93
Discovery: 1878; by Cleve in Uppsala, Sweden
Note: shiny metal; used for making very strong magnets
Name: Erbium Symbol: Er
Atomic Number: 68 Atomic Weight: 167.26
Discovery: 1842; Mosander; Stockholm, Sweden
Note: shiny, gray metal; reacts slowly with air and water; used to make infrared filters; used with titanium to make strong alloys
Name: Thulium Symbol: Tm
Atomic Number: 69 Atomic Weight: 168.93
Discovery: 1879; by Cleve in Uppsala, Sweden
Note: very rare, shiny metal; few uses; used as radiation source in X-ray machines
Name: Ytterbium Symbol: Yb
Atomic Number: 70 Atomic Weight: 173.04
Discovery: 1878; deMarignac; Geneva, Switzerland
Note: soft metal; reacts slowly with air and oxygen; used in manufacturing tools
Name: Lutetium Symbol: Lu
Atomic Number: 71 Atomic Weight: 174.97
Discovery: 1907; by Urbain in Paris, France
Note: very hard and dense metal; very rare; rarely used, except in science research
Name: Thorium Symbol: Th
Atomic Number: 90 Atomic Weight: 232.04
Discovery: 1829; Berzelius; Stockholm, Sweden
Note: shiny metal; radioactive; used as nuclear fuel and in camping lantern mantles
Name: Protactinium Symbol: Pa
Atomic Number: 91 Atomic Weight: 231.04
Discovery: 1917; Hahn & Meitner; Berlin, Germany
Note: shiny metal; radioactive; found in uranium ore; extremely rare; rarely used
Name: Uranium Symbol: U
Atomic Number: 92 Atomic Weight: 238.03
Discovery: 1789; Klaproth; Berlin, Germany
Note: soft, shiny metal; radioactive; reacts with oxygen; used as nuclear fuel
Name: Neptunium Symbol: Np
Atomic Number: 93 Atomic Weight: 237.05
Discovery: 1940; McMillan; Berkeley, California
Note: shiny metal; does not occur naturally; by-product of uranium fuel
Name: Plutonium Symbol: Pu
Atomic Number: 94 Atomic Weight: 244
Discovery: 1940; Seaborg; Berkeley, California
Note: shiny metal; radioactive; does not occur naturally; used as nuclear fuel source and in nuclear weapons; obtained from uranium fueled reactors
Name: Americium Symbol: Am
Atomic Number: 95 Atomic Weight: 243
Discovery: 1944; Seaborg; Chicago, Illinois
Note: shiny metal; radioactive; very rare; does not occur naturally; made by bombarding plutonium with neutrons
Name: Curium Symbol: Cm
Atomic Number: 96 Atomic Weight: 247
Discovery: 1944; Seaborg; Berkeley, California
Note: shiny metal; radioactive; very rare; does not occur naturally; made by bombarding plutonium with neutrons
Name: Berkelium Symbol: Bk
Atomic Number: 97 Atomic Weight: 247
Discovery: 1949; Thompson; Berkeley, California
Note: shiny metal; radioactive; very rare; does not occur naturally; made by bombarding plutonium with neutrons
Name: Californium Symbol: Cf
Atomic Number: 98 Atomic Weight: 251
Discovery: 1950; Thompson; Berkeley, California
Note: shiny metal; radioactive; extremely rare; does not occur naturally; made by bombarding plutonium with neutrons; used in cancer treatment
Name: Einsteinium Symbol: Es
Atomic Number: 99 Atomic Weight: 252
Discovery: 1952; Choppin; Berkeley, California
Note: shiny metal; radioactive; very rare; does not occur naturally; made by bombarding plutonium with neutrons
Name: Fermium Symbol: Fm
Atomic Number: 100 Atomic Weight: 257
Discovery: 1952; Choppin; Berkeley, California
Note: metal; radioactive; does not occur naturally; made by bombarding plutonium with neutrons; only a few millionths of a gram have been produced
Name: Mendelevium Symbol: Md
Atomic Number: 101 Atomic Weight: 258
Discovery: 1955; Ghiorso; Berkeley, California
Note: metal; radioactive; does not occur naturally; made by bombarding einsteinium with alpha particles, (helium nucleus with two protons and two neutrons); only a few atoms have been produced
Name: Nobelium Symbol: No
Atomic Number: 102 Atomic Weight: 259
Discovery: 1958; Ghiorso; Berkeley, California
Note: metal; radioactive; does not occur naturally; made by bombarding Curium atoms with carbon nuclei; only a few atoms have been produced
Name: Lawrencium Symbol: Lr
Atomic Number: 103 Atomic Weight: 260
Discovery: 1961; Ghiorso; Berkeley, California
Note: metal; radioactive; does not occur naturally; made by bombarding Californium atoms with boron nuclei; only a few atoms have been produced