<small>[[Chemistry]] | [[19th Century]]</small> | | | |---|---| |Atomic Mass|[10.81 u](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Atomic-Weight)| |Standard State|[solid](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Physical-Description)| |Electron Configuration|[[He]2s22p1](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Electron-Configuration)| |Oxidation States|[+3](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Oxidation-States)| |Electronegativity (Pauling Scale)|[2.04](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Electronegativity)| |Atomic Radius (van der Waals)|[192 pm](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Atomic-Radius)| |Ionization Energy|[8.298 eV](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Ionization-Energy)| |Electron Affinity|[0.277 eV](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Electron-Affinity)| |Melting Point|[2348 K](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Melting-Point)| |Boiling Point|[4273 K](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Boiling-Point)| |Density|[2.37 g/cm³](https://pubchem.ncbi.nlm.nih.gov/element/5#section=Density)| |Year Discovered|[1808](https://pubchem.ncbi.nlm.nih.gov/element/5#section=History)|