Aluminum vs Silicon

Side-by-side comparison of Aluminum (Al, element 13) and Silicon (Si, element 14) by atomic structure and physical properties.

← Back to Periodic Table
PropertyAl Aluminum Si Silicon
Atomic number1314
SymbolAlSi
NameAluminumSilicon
Categorypost-transition-metalmetalloid
Standard Atomic Weight26.981538 u28.085 u
Period33
Group1314
Blockpp
Phase at STPSolidSolid
Electron configuration[Ne]3s23p1[Ne]3s23p2
Oxidation states[-2, -1, 0, 1, 2, 3][-4, -3, -2, -1, 0, 1, 2, 3, 4]
Electronegativity (Pauling)1.611.9
Electron affinity0.4328 eV1.385 eV
Density2700 kg/m³2329.6 kg/m³
Melting point660.287 °C1413.85 °C
Boiling point2518.85 °C3264.85 °C
Discovery year18251824

Key Differences

PropertyAl AluminumSi Silicon
Standard Atomic Weight26.981538 u ↓ lower28.085 u ↑ higher
Density2700 kg/m³ ↑ higher2329.6 kg/m³ ↓ lower
Melting point660.287 °C ↓ lower1413.85 °C ↑ higher
Boiling point2518.85 °C ↓ lower3264.85 °C ↑ higher
Electronegativity (Pauling)1.61 ↓ lower1.9 ↑ higher
Electron affinity0.4328 eV ↓ lower1.385 eV ↑ higher
Group13 14
Categorypost-transition-metal metalloid
Electron configuration[Ne]3s23p1 [Ne]3s23p2
Discovery year1825 1824