11Na22.990
Sodium (Na)
Element 11 Ā· Alkali metal
Sodium (Na) is a chemical element with atomic number 11. It is classified as an alkali metal in period 3, group 1 of the periodic table (the s-block). Its standard atomic weight is 22.990 u and its ground-state electron configuration is [Ne] 3sĀ¹.
Sodium facts
| Atomic number (Z) | 11 |
|---|---|
| Symbol | Na |
| Standard atomic weight | 22.990 u |
| Category | Alkali metal |
| Group | 1 |
| Period | 3 |
| Block | s-block |
| Electron configuration | [Ne] 3sĀ¹ |
| Electronegativity (Pauling) | 0.93 |
| State at 20 Ā°C | Solid |
| Protons / electrons | 11 / 11 |
| Neutrons (most common isotope, approx.) | 12 |
| Molar mass | 22.99 g/mol |