1 H hydrogen ? 2 He helium ?3 Li lithium ?4 Be beryllium ? 5 B boron ?6 C carbon ?7 N nitrogen ?8 O oxygen ?9 F fluorine ?10 Ne neon ?11 Na sodium ?12 Mg magnesium ? 13 Al aluminium ?14 Si silicon ?15 P phosphorus ?16 S sulfur ?17 Cl chlorine ?18 Ar argon ?19 K potassium ?20 Ca calcium ?21 Sc scandium ?22 Ti titanium ?23 V vanadium ?24 Cr chromium ?25 Mn manganese ?26 Fe iron ?27 Co cobalt ?28 Ni nickel ?29 Cu copper ?30 Zn zinc ?31 Ga gallium ?32 Ge germanium ?33 As arsenic ?34 Se selenium ?35 Br bromine ?36 Kr krypton ?37 Rb rubidium ?38 Sr strontium ?39 Y yttrium ?40 Zr zirconium ?41 Nb niobium ?42 Mo molybdenum ?43 Tc technetium 97 (most stable isotope)44 Ru ruthenium ?45 Rh rhodium ?46 Pd palladium ?47 Ag silver ?48 Cd cadmium ?49 In indium ?50 Sn tin ?51 Sb antimony ?52 Te tellurium ?53 I iodine ?54 Xe xenon ?55 Cs caesium ?56 Ba barium ?57 La lanthanum ?72 Hf hafnium ?73 Ta tantalum ?74 W tungsten ?75 Re rhenium ?76 Os osmium ?77 Ir iridium ?78 Pt platinum ?79 Au gold ?80 Hg mercury ?81 Tl thallium ?82 Pb lead ?83 Bi bismuth ?84 Po polonium 209 (most stable isotope)85 At astatine 210 (most stable isotope)86 Rn radon 222 (most stable isotope)87 Fr francium 223 (most stable isotope)88 Ra radium 226 (most stable isotope)89 Ac actinium 227 (most stable isotope)104 Rf rutherfordium 267 (most stable isotope)105 Db dubnium 268 (most stable isotope)106 Sg seaborgium 269 (most stable isotope)107 Bh bohrium 270 (most stable isotope) (unconfirmed: 278)108 Hs hassium 270 (most stable isotope)109 Mt meitnerium 278 (most stable isotope) (unconfirmed: 282)110 Ds darmstadtium 281 (most stable isotope)111 Rg roentgenium 282 (most stable isotope) (unconfirmed: 286)112 Cn copernicium 285 (most stable isotope)113 Nh nihonium 286 (most stable isotope)114 Fl flerovium 289 (most stable isotope) (unconfirmed: 290)115 Mc moscovium 290 (most stable isotope)116 Lv livermorium 293 (most stable isotope)117 Ts tennessine 294 (most stable isotope)118 Og oganesson 294 (most stable isotope) (unconfirmed: 295) 58 Ce cerium ?59 Pr praseodymium ?60 Nd neodymium ?61 Pm promethium 145 (most stable isotope)62 Sm samarium ?63 Eu europium ?64 Gd gadolinium ?65 Tb terbium ?66 Dy dysprosium ?67 Ho holmium ?68 Er erbium ?69 Tm thulium ?70 Yb ytterbium ?71 Lu lutetium ? 90 Th thorium ?91 Pa protactinium ?92 U uranium ?93 Np neptunium 237 (most stable isotope)94 Pu plutonium 244 (most stable isotope)95 Am americium 243 (most stable isotope)96 Cm curium 247 (most stable isotope)97 Bk berkelium 247 (most stable isotope)98 Cf californium 251 (most stable isotope)99 Es einsteinium 252 (most stable isotope)100 Fm fermium 257 (most stable isotope)101 Md mendelevium 258 (most stable isotope)102 No nobelium 259 (most stable isotope)103 Lr lawrencium 266 (most stable isotope)