1 H Hydrogen 1.00794 2 He Helium 4.002602 3 Li Lithium 6.941 4 Be Beryllium 9.012182 5 B Boron 10.811 6 C Carbon 12.0107 7 N Nitrogen 14.0067 8 O Oxygen 15.9994 9 F Fluorine 18.9984032 10 Ne Neon 20.1797 11 Na Sodium 22.989770 12 Mg Magnesium 24.3050 13 Al Aluminum 26.981538 14 Si Silicon 28.0855 15 P Phosphorus 30.973761 16 S Sulfur 32.065 17 Cl Chlorine 35.453 18 Ar Argon 39.948 19 K Potassium 39.0983 20 Ca Calcium 40.078 21 Sc Scandium 44.955910 22 Ti Titanium 47.867 23 V Vanadium 50.9415 24 Cr Chromium 51.9961 25 Mn Manganese 54.938049 26 Fe Iron 55.845 27 Co Cobalt 58.933200 28 Ni Nickel 58.6934 29 Cu Copper 63.546 30 Zn Zinc 65.409 31 Ga Gallium 69.723 32 Ge Germanium 72.64 33 As Arsenic 74.92160 34 Se Selenium 78.96 35 Br Bromine 79.904 36 Kr Krypton 83.798 37 Rb Rubidium 85.4678 38 Sr Strontium 87.62 39 Y Yttrium 88.90585 40 Zr Zirconium 91.224 41 Nb Niobium 92.90638 42 Mo Molybdenum 95.94 43 Tc Technetium 98 44 Ru Ruthenium 101.07 45 Rh Rhodium 102.90550 46 Pd Palladium 106.42 47 Ag Silver 107.8682 48 Cd Cadmium 112.411 49 In Indium 114.818 50 Sn Tin 118.710 51 Sb Antimony 121.760 52 Te Tellurium 127.60 53 I Iodine 126.90447 54 Xe Xenon 131.293 55 Cs Cesium 132.90545 56 Ba Barium 137.327 57 La Lanthanum 138.9055 58 Ce Cerium 140.116 59 Pr Praseodymium 140.90765 60 Nd Neodymium 144.24 61 Pm Promethium 145 62 Sm Samarium 150.36 63 Eu Europium 151.964 64 Gd Gadolinium 157.25 65 Tb Terbium 158.92534 66 Dy Dysprosium 162.500 67 Ho Holmium 164.93032 68 Er Erbium 167.259 69 Tm Thulium 168.93421 70 Yb Ytterbium 173.04 71 Lu Lutetium 174.967 72 Hf Hafnium 178.49 73 Ta Tantalum 180.9479 74 W Tungsten 183.84 75 Re Rhenium 186.207 76 Os Osmium 190.23 77 Ir Iridium 192.217 78 Pt Platinum 195.078 79 Au Gold 196.96655 80 Hg Mercury 200.59 81 Tl Thallium 204.3833 82 Pb Lead 207.2 83 Bi Bismuth 208.98038 84 Po Polonium 209 85 At Astatine 210 86 Rn Radon 222 87 Fr Francium 223 88 Ra Radium 226 89 Ac Actinium 227 90 Th Thorium 232.0381 91 Pa Protactinium 231.03588 92 U Uranium 238.02891 93 Np Neptunium 237 94 Pu Plutonium 244 95 Am Americium 243 96 Cm Curium 247 97 Bk Berkelium 247 98 Cf Californium 251 99 Es Einsteinium 252 100 Fm Fermium 257 101 Md Mendelevium 258 102 No Nobelium 259 103 Lr Lawrencium 262 104 Rf Rutherfordium 261 105 Db Dubnium 262 106 Sg Seaborgium 266 107 Hs Hassium 264 108 Bh Bohrium 277 109 Mt Meitnerium 268 110 Ds Darmstadtium 281 111 Rg Roentgenium 272 112 Cn Cpernicium 285 113 Uut Ununtrium 284 114 Fl Flerovium 289 115 Uup Ununpentium 288 116 Lv Livermorium 293 117 Uus Ununseptium 294 118 Uuo Ununoctium 294