Hydrogen vs Strontium

PropertyH HydrogenSr Strontium
Atomic number138
SymbolHSr
NameHydrogenStrontium
Categorynonmetalalkaline-earth-metal
Standard Atomic Weight1.007975 u87.62 u
Period15
Group12
Blockss
Phase at STPgassolid
Electron configuration1s1[Kr]5s2
Oxidation states[-1, 1][1, 2]
Electronegativity (Pauling)2.20.95
Electron affinity0.75419 eV0.052 eV
Density0.08988 kg/m³2640 kg/m³
Melting point-259.34 °C776.85 °C
Boiling point-252.87 °C1381.85 °C
Discovery year17661792