NaCl
Sodium chloride (NaCl)
Also known as: table salt, halite, rock salt
Sodium chloride is the textbook ionic compound: a lattice of alternating Na⁺ and Cl⁻ ions held together by electrostatic attraction, with no individual molecules at all. It forms when a violently reactive metal meets a toxic green gas — and the product seasons your food. Dissolved in water, its freed ions conduct electricity, making brine the classic electrolyte.
Molar mass breakdown
58.4398 g/mol| Element | Atoms | Mass (g/mol) | % by mass |
|---|---|---|---|
| Chlorine (Cl) | 1 | 35.45 | 60.66% |
| Sodium (Na) | 1 | 22.99 | 39.34% |
What sodium chloride is used for
- Food seasoning and preservation
- De-icing roads
- Raw material for chlorine, sodium hydroxide and sodium metal
- Saline solutions in medicine (0.9% NaCl matches body fluids)
Key facts
- Molar mass ≈ 58.44 g/mol.
- Melts at 801 °C — typical of ionic lattices' strong bonding.
- Seawater is about 3.5% dissolved salts, mostly NaCl.
Frequently asked questions
What is the molar mass of NaCl?
About 58.44 g/mol: 22.990 (Na) + 35.45 (Cl).
Why does salt dissolve in water?
Polar water molecules surround and stabilise the individual Na⁺ and Cl⁻ ions, pulling the lattice apart — a process called hydration.
Is NaCl a molecule?
Not in the solid — it is a continuous ionic lattice. “NaCl” is a formula unit expressing the 1:1 ion ratio.