Characteristic
Tripotassium phosphate, also called potassium phosphate tribasic, is a water-soluble salt which has the chemical formula K3PO4.(H2O)x (x = 0, 3, 7, 9) Tripotassium phosphate is a strong base.
Chemical formula:K3PO4
Molar mass:212.27 g/mol
Appearance:White deliquescent powder
Density:2.564 g/cm3 (17 °C)
Melting point:1,380 °C (2,520 °F; 1,650 K)
Solubility in water:90 g/100 mL (20 °C)
Solubility in ethanol:Insoluble
Basicity (pKb):1.6
Crystal structure:Primitive orthorhombic
Application
Potassium phosphate is used as a fertilizer and food additive. It serves as a buffering agent to regulate pH. It is also used in optical modulators and for non-linear optics such as second-harmonic generation (SHG). It is involved in the phase-transfer catalyzed preparation of acetylenes from the corresponding vicinal dibromo compounds through double dehydrobromination. It is also useful for the oxidative coupling of thiols to disulfide.