Potassium Chloride is a high purity, dry crystalline inorganic/metal halide salt composed of potassium and chlolrine, KCl. It has a molar mass of 74.551 g/mol and occurs naturally as the mineral slyvite. Potassium chloride is often referred to as muriate of potash (MOP), particularly when used as a fertilizer.
Potassium Chloride also used as a water softener.
	• Primarily used as a shale inhibitor as the potassium ion exchanges with calcium and sodium ions n the interlayer space in illites and smectites, converting them to more stable mica-type structures that do not hydrate and swell.
	• Used to prepare brines for drill-in, completion, and workover fluids
| Other names | 
						Sylvite common name | 
| Identifiers | |
| CAS number | [7447-40-7] | 
| RTECS number | TS8050000 | 
| ChemSpiderID | 4707 | 
| Properties | |
| Molecular formula | KCl | 
| Molar mass | 74.55 g/mol | 
| Appearance | white crystalline solid | 
| Density | 1.987 g/cm3 | 
| Melting point | 775 °C | 
| Boiling point | ca. 1500 °C | 
| Solubilityin water | 
						28.1 g/100 ml (0 °C) | 
| Hazards | |
| MSDS | ICSC 1450 | 
| EU Index | Not listed | 
| Flash point | Non-flammable | 
| LD50 | 2600 mg/kg (oral/rat), 142 mg/kg (intravenous/rat) |