<small>[[Chemistry]]| [[19th Century]]</small> | | | |---|---| |Atomic Mass|[132.9054520 u](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Atomic-Weight)| |Standard State|[solid](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Physical-Description)| |Electron Configuration|[[Xe]6s1](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Electron-Configuration)| |Oxidation States|[+1](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Oxidation-States)| |Electronegativity (Pauling Scale)|[0.79](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Electronegativity)| |Atomic Radius (van der Waals)|[343 pm](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Atomic-Radius)| |Ionization Energy|[3.894 eV](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Ionization-Energy)| |Electron Affinity|[0.472 eV](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Electron-Affinity)| |Melting Point|[301.59 K](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Melting-Point)| |Boiling Point|[944 K](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Boiling-Point)| |Density|[1.93 g/cm³](https://pubchem.ncbi.nlm.nih.gov/element/55#section=Density)| |Year Discovered|[1860](https://pubchem.ncbi.nlm.nih.gov/element/55#section=History)|