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31Ga69.723
Gallium
Post-Transition MetalGallium is a chemical element with symbol Ga and atomic number 31. Elemental gallium does not occur in free form in nature, but as the gallium(III) compounds that are in trace amounts in zinc ores and in bauxite. Gallium is a soft, silvery metal, and elemental gallium is a brittle solid at low temperatures, and melts at 29.76 °C (85.57 °F) (slightly above room temperature).
Phase: SolidAppearance: silver-white
2, 8, 18, 3
Physical Properties
Atomic Mass69.7231 u
Density5.91 g/cm³
Melting Point302.9146 K
Boiling Point2673 K
Molar Heat25.86 J/(mol·K)
Period4
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1
Semantic Config[Ar] 3d10 4s2 4p1
Shells2, 8, 18, 3
Electron Affinity41 kJ/mol
Electronegativity1.81
Ionization Energies
IE1: 578.8 kJ/molIE2: 1979.3 kJ/molIE3: 2963 kJ/molIE4: 6180 kJ/mol
Discovery
Discovered byLecoq de Boisbaudran