68Er167.26

Erbium (Er) – element 68

Erbium is a chemical element with the symbol Er and atomic number 68. It is a lanthanide in group 3 (lanthanides), period 6 of the periodic table (f-block), and is a solid at room temperature.

Erbium (Er) has atomic number 68, atomic mass 167.26 u and electron configuration [Xe] 4f12 6s2.

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Erbium facts

SymbolEr
Atomic number68
Atomic mass167.26 u (g/mol)
Categorylanthanide
Groupgroup 3 (lanthanides)
Period6
Blockf-block
Phase at 20 °CSolid
Electron configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f12
Noble-gas notation[Xe] 4f12 6s2
Electrons per shell2, 8, 18, 30, 8, 2

Bohr model and shells

Er

Erbium has 68 electrons in 6 shells: 2, 8, 18, 30, 8, 2. Full configuration and noble-gas notation are in the table; work out any element or ion with the electron configuration calculator.

Physical and atomic properties

Melting point1802 K (1528.8 °C)
Boiling point3141 K (2867.8 °C)
Density9.066 g/cm³
Electronegativity (Pauling)1.24
Electron affinity30.1 kJ/mol
Ionization energies589.3, 1150, 2194 kJ/mol (1st, 2nd, 3rd)
Molar heat capacity28.12 J/(mol·K)
Discovered byCarl Gustaf Mosander

Use the atomic mass in the molar mass calculator for any formula containing Er.

Position in the periodic table

HydrogenHHeliumHeLithiumLiBerylliumBeBoronBCarbonCNitrogenNOxygenOFluorineFNeonNeSodiumNaMagnesiumMgAluminiumAlSiliconSiPhosphorusPSulfurSChlorineClArgonArPotassiumKCalciumCaScandiumScTitaniumTiVanadiumVChromiumCrManganeseMnIronFeCobaltCoNickelNiCopperCuZincZnGalliumGaGermaniumGeArsenicAsSeleniumSeBromineBrKryptonKrRubidiumRbStrontiumSrYttriumYZirconiumZrNiobiumNbMolybdenumMoTechnetiumTcRutheniumRuRhodiumRhPalladiumPdSilverAgCadmiumCdIndiumInTinSnAntimonySbTelluriumTeIodineIXenonXeCesiumCsBariumBaLanthanumLaCeriumCePraseodymiumPrNeodymiumNdPromethiumPmSamariumSmEuropiumEuGadoliniumGdTerbiumTbDysprosiumDyHolmiumHoErbiumErThuliumTmYtterbiumYbLutetiumLuHafniumHfTantalumTaTungstenWRheniumReOsmiumOsIridiumIrPlatinumPtGoldAuMercuryHgThalliumTlLeadPbBismuthBiPoloniumPoAstatineAtRadonRnFranciumFrRadiumRaActiniumAcThoriumThProtactiniumPaUraniumUNeptuniumNpPlutoniumPuAmericiumAmCuriumCmBerkeliumBkCaliforniumCfEinsteiniumEsFermiumFmMendeleviumMdNobeliumNoLawrenciumLrRutherfordiumRfDubniumDbSeaborgiumSgBohriumBhHassiumHsMeitneriumMtDarmstadtiumDsRoentgeniumRgCoperniciumCnNihoniumNhFleroviumFlMoscoviumMcLivermoriumLvTennessineTsOganessonOg

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Frequently asked questions

What is the atomic mass of erbium?

The atomic mass of erbium is 167.26 u, so one mole of erbium atoms weighs 167.26 g.

What is the electron configuration of erbium?

Erbium has 68 electrons: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹², or [Xe] 4f¹² 6s² in noble-gas notation. Electrons per shell: 2, 8, 18, 30, 8, 2.

Is erbium a metal?

Yes. Erbium is a lanthanide.

Where is erbium on the periodic table?

Erbium is in group 3 (lanthanides), period 6, in the f-block.

Data: Periodic-Table-JSON (CC BY-SA 3.0); standard atomic weights from IUPAC (abridged). Values in brackets are the mass number of the longest-lived isotope.