Atomic Element Z = 11 • Alkali Metal

Sodium (Na) — Atomic Data, Electron Shells & Reactions

Sodium (symbol Na, atomic number 11) has a standard atomic weight of 22.99 u and ground-state configuration [Ne] 3s1.

IUPAC Physical & Atomic Properties

Atomic Number (Z) 11 IUPAC Symbol Na Standard Atomic Weight 22.99 g/mol Period / Group / Block 3 / 1 / s-block Condensed Electron Config [Ne] 3s1 Full Subshell Config 1s2 2s2 2p6 3s1 Principal Shell Occupancy [2, 8, 1] Pauling Electronegativity 0.93 First Ionization Energy 496 kJ/mol Covalent Radius 166 pm Melting Point 370.94 K (97.79 °C) Boiling Point 1156 K (882.85 °C) Density 0.971 g/cm³ Oxidation States +1

Bohr Shell Diagram & Balanced Reactions

Na (Z=11) — Valence shell highlighted in vermilion

Interactive Stoichiometry Reactions Involving Sodium:

H2SO4 + NaOH -> Na2SO4 + H2O Na + H2O -> NaOH + H2 NaHCO3 + CH3COOH -> CH3COONa + H2O + CO2 I2 + Na2S2O3 -> NaI + Na2S4O6