Each element is classified according to these 10 categories; select each classification for more information.
Alkali Metal | Alkaline Earth Metal | Transition Metal | Post-Transition Metal | Semi-Metal |
Non-Metal | Halogen | Noble Gas | Lanthanide | Actinide |
Group →(old)Period ↓ | 1(IA; 1A) | 2(IIA; 2A) | 3(IIIB; 3B) | 4(IVB; 4B) | 5(VB; 5B) | 6(VIB; 6B) | 7(VIIB; 7B) | 8(VIII; 8) | 9(VIII; 8) | 10(VIII; 8) | 11(IB; 1B) | 12(IIB; 2B) | 13(IIIA; 3A) | 14(IVA; 4A) | 15(VA; 5A) | 16(VIA; 6A) | 17(VIIA; 7A) | 18(VIIIA; 8A) |
1 | 1HHydrogen1.008 | 2HeHelium4.003 | ||||||||||||||||
2 | 3LiLithium6.941 | 4BeBeryllium9.012 | Legend: | Atomic #SymbolNameAtomic wt. | State: | SolidGasLiquidSynthetic | 5BBoron10.81 | 6CCarbon12.01 | 7NNitrogen14.01 | 8OOxygen16.00 | 9FFluorine19.00 | 10NeNeon20.18 | ||||||
3 | 11NaSodium22.99 | 12MgMagnesium24.31 | 13AlAluminum26.98 | 14SiSilicon28.09 | 15PPhosphorus30.97 | 16SSulfur32.07 | 17ClChlorine35.45 | 18ArArgon39.95 | ||||||||||
4 | 19KPotassium39.10 | 20CaCalcium40.08 | 21ScScandium44.96 | 22TiTitanium47.88 | 23VVanadium50.94 | 24CrChromium52.00 | 25MnManganese54.94 | 26FeIron55.85 | 27CoCobalt58.47 | 28NiNickel58.69 | 29CuCopper63.55 | 30ZnZinc65.39 | 31GaGallium69.72 | 32GeGermanium72.59 | 33AsArsenic74.92 | 34SeSelenium78.96 | 35BrBromine79.90 | 36KrKrypton83.80 |
5 | 37RbRubidium85.47 | 38SrStrontium87.62 | 39YYttrium88.91 | 40ZrZirconium91.22 | 41NbNiobium92.91 | 42MoMolybdenum95.94 | 43TcTechnetium(98) | 44RuRuthenium101.1 | 45RhRhodium102.9 | 46PdPalladium106.4 | 47AgSilver107.9 | 48CdCadmium112.4 | 49InIndium114.8 | 50SnTin118.7 | 51SbAntimony121.8 | 52TeTellurium127.6 | 53IIodine126.9 | 54XeXenon131.3 |
6 | 55CsCesium132.9 | 56BaBarium137.3 | Lanthanides57-71 | 72HfHafnium178.5 | 73TaTantalum180.9 | 74WTungsten183.9 | 75ReRhenium186.2 | 76OsOsmium190.2 | 77IrIridium190.2 | 78PtPlatinum195.1 | 79AuGold197.0 | 80HgMercury200.5 | 81TlThallium204.4 | 82PbLead207.2 | 83BiBismuth209.0 | 84PoPolonium(210) | 85AtAstatine(210) | 86RnRadon(222) |
7 | 87FrFrancium(223) | 88RaRadium(226) | Actinides89-103 | 104RfRutherfordium(257) | 105DbDubnium(260) | 106SgSeaborgium(263) | 107BhBohrium(265) | 108HsHassium(265) | 109MtMeitnerium(266) | 110DsDarmstadtium(271) | 111RgRoentgenium(272) | 112CnCopernicum(277) | 113UutUnuntrium-- | 114FlFlerovium(296) | 115UupUnunpentium-- | 116LvLivermorium(298) | 117UusUnunseptium-- | 118UuoUnunoctium-- |
57LaLanthanum138.9 | 58CeCerium140.1 | 59PrPraseodymium140.9 | 60NdNeodymium144.2 | 61PmPromethium(147) | 62SmSamarium150.4 | 63EuEuropium152.0 | 64GdGadolinium157.3 | 65TbTerbium158.9 | 66DyDysprosium162.5 | 67HoHolmium164.9 | 68ErErbium167.3 | 69TmThulium168.9 | 70YbYtterbium173.0 | 71LuLutetium175.0 |
89AcActinium(227) | 90ThThorium232.0 | 91PaProtactinium(231) | 92UUranium(238) | 93NpNeptunium(237) | 94PuPlutonium(242) | 95AmAmericium(243) | 96CmCurium(247) | 97BkBerkelium(247) | 98CfCalifornium(249) | 99EsEinsteinium(254) | 100FmFermium(253) | 101MdMendelevium(256) | 102NoNobelium(254) | 103LrLawrencium(257) |
Atomic masses in parentheses indicate the isotope with the longest half-life for elements with no stable isotopes.