SHEET /vs/sodium-chloride-vs-potassium-chloride · COMPARISON
Sodium chloride vs Potassium chloride: what is the difference?
How they differ
Both are simple salts of chloride and both taste salty, and only sodium chloride tastes purely so. Potassium chloride is the main ingredient in the salt substitutes sold as NoSalt and LoSalt, and it carries a metallic, faintly bitter edge that gets stronger with concentration, which is why substitutes are usually blends rather than straight potassium chloride. The saltiness is read by different mechanisms: the sodium ion passes through an ion channel on the taste cell directly, and the potassium ion is a poorer fit for it. The reported oral LD50 values differ sharply, 3000 mg/kg in rats for table salt against 383 mg/kg in mice for potassium chloride, measured in different species but pointing at a real difference: potassium load matters to the heart in a way sodium load does not.
Side by side
| Sodium chloride | Potassium chloride | |
|---|---|---|
| Formula | ClNa | ClK |
| Molecular weight | 58.44 g/mol | 74.55 g/mol |
| Family | Other | Other |
| Everyday group | Food & flavor | Food & flavor |
| Functional groups | Halogenated | Halogenated |
| GHS signal wordThe supplier-filed hazard label, not a statement about ordinary use. | Danger | not recorded |
| Oral LD50A single acute animal measure. It ranks nothing about human safety. | 3,000 mg/kg (oral, rat) | 383 mg/kg (oral, mouse) |
| Found in | Hot sauce, Cheese, Bread, Cured meat, Soy sauce, Processed snacks | not recorded |
| CAS number | 7647-14-5 | 7447-40-7 |
| PubChem CID | 5234 | 4873 |
Common questions
- What is the difference between Sodium chloride and Potassium chloride?
- Both are simple salts of chloride and both taste salty, and only sodium chloride tastes purely so. Potassium chloride is the main ingredient in the salt substitutes sold as NoSalt and LoSalt, and it carries a metallic, faintly bitter edge that gets stronger with concentration, which is why substitutes are usually blends rather than straight potassium chloride. The saltiness is read by different mechanisms: the sodium ion passes through an ion channel on the taste cell directly, and the potassium ion is a poorer fit for it.
- Is Sodium chloride bigger than Potassium chloride?
- Potassium chloride is the heavier molecule, 74.55 g/mol against 58.44 g/mol for Sodium chloride. Sodium chloride is ClNa and Potassium chloride is ClK.
- Which has the lower reported LD50, Sodium chloride or Potassium chloride?
- Potassium chloride, at 383 mg/kg (oral, mouse), against 3,000 mg/kg (oral, rat) for Sodium chloride. An LD50 is one acute animal measurement, and the two here were not necessarily measured in the same species, so it is a data point rather than a ranking of how dangerous either is to a person.
Read the full records: Sodium chloride and Potassium chloride.