The Periodic Table of Elements 1 6 H C HYDROGEN 1 3 4 Li Be LITHIUM BERYLLIUM 7 9 11 5 CARBON Atomic Weight = Number of Protons + Number of Neutrons METALS MAGNESIUM 23 24 20 21 22 23 24 K Ca Sc Ti V POTASSIUM CALCIUM SCANDIUM TITANIUM VANADIUM 39 37 40 38 45 39 48 40 Rb Sr Y Zr RUBIDIUM STRONTIUM YTTRIUM ZIRCONIUM 88 89 85 55 56 52 55 43 96 74 Ni NICKEL 59 RHODIUM 101 76 Ba Hf Ta W Re Os Ir Pt BARIUM HAFNIUM TANTALUM TUNGSTEN RHENIUM OSMIUM IRIDIUM PLATINUM 133 137 88 181 105 184 106 186 107 190 108 O F Ne OXYGEN FLUORINE NEON 11 12 14 16 19 Ra Rf Db Sg Bh RADIUM RUTHERFORDIUM DUBNIUM SEABORGIUM BOHRIUM HASSIUM 223 226 261 262 266 264 269 = Solid at room temperature 57 = Radioactive = Artificially Made 59 Ce LANTHANUM CERIUM 139 140 = Liquid at room temperature = Gas at room temperature 58 La 89 90 60 Pr 195 110 15 108 Si P S Cl Ar SILICON PHOSPHORUS SULFUR CHLORINE ARGON 28 32 GOLD 197 111 GALLIUM MERCURY 201 112 In Sn TIN 115 61 144 92 268 62 145 93 Ac Th Pa U ACTINIUM THORIUM PROTACTINIUM URANIUM 227 232 231 238 40 36 Se Br Kr SELENIUM BROMINE KRYPTON 75 79 52 Sb Te 122 83 80 53 ANTIMONY TELLURIUM 119 82 35 35 As 51 INDIUM 32 34 ARSENIC 73 50 I Xe IODINE XENON 128 84 84 54 127 85 131 86 Tl Pb Bi Po At Rn THALLIUM LEAD BISMUTH POLONIUM ASTATINE RADON 204 113 207 114 269 63 272 64 277 65 NOT YET OBSERVED 66 285 67 209 115 209 116 210 117 222 118 70 293 71 Er Tm Yb Lu GADOLINIUM TERBIUM DYSPROSIUM HOLMIUM ERBIUM THULIUM YTTERBIUM LUTETIUM 157 159 163 165 167 169 173 175 95 96 97 98 Np Pu Am Cm Bk 244 69 NOT YET OBSERVED 152 NEPTUNIUM PLUTONIUM AMERICIUM 237 289 EUROPIUM 150 94 NOT YET OBSERVED 68 Nd Pm Sm Eu Gd Tb Dy Ho 141 31 33 GERMANIUM 70 81 Au Hg 20 18 Al 112 80 17 ALUMINUM 49 CADMIUM 16 MEITNERIUM UNUNNILIUM UNUNUNIUM UNUNBIUM UNUNTRIUM UNUNQUADIUM UNUNPENTIUM UNUNHEXIUM UNUNSEPTIUM UNUNOCTIUM PRASEODYMIUM NEODYMIUM PROMETHIUM SAMARIUM 91 14 Hs Mt Uun Uuu Uub Uut Uuq Uup Uuh Uus Uuo Fr FRANCIUM KEY 192 109 SILVER 79 Cs 87 N NITROGEN 65 48 Ag Cd 106 78 CESIUM 178 104 64 10 C 31 ZINC COPPER 47 PALLADIUM 103 77 30 4 9 CARBON Cu Zn Ga Ge 59 46 Ru Rh Pd 98 75 Co 45 MOLYBDENUM TECHNETIUM RUTHENIUM 93 29 COBALT 56 44 Nb Mo Tc 73 IRON 28 8 B 27 27 Cr Mn Fe 42 NIOBIUM 91 72 26 CHROMIUM MANGANESE 51 41 25 7 HELIUM BORON 13 Na Mg 19 6 Chemical Name 12 He NON-METALS Chemical Symbol 12 SODIUM 2 Atomic Number = Number of Protons = Number of Electrons 243 CURIUM 247 99 Cf 100 251 102 Es Fm Md No BERKELIUM CALIFORNIUM EINSTEINIUM 247 101 252 FERMIUM 257 MENDELEVIUM NOBELIUM 258 259 103 Lr LAWRENCIUM 262