Potassium Sodium L-Tartrate Tetrahydrate 99%
Potassium sodium tartrate tetrahydrate, also known as Rochelle salt, is a double salt of tartaric acid. Potassium sodium tartrate and monopotassium phosphate were the first materials discovered to exhibit piezoelectricity.This property led to its extensive use in "crystal" gramophone (phono) pick-ups, microphones and earpieces during the post-World War II consumer electronics boom of the mid-20th Century. Such transducers had an exceptionally high output with typical pick-up cartridge outputs as much as 2 volts or more. Rochelle salt is deliquescent so any transducers based on the material deteriorated if stored in damp conditions.
|Molar mass||282.1 g/mol|
|Appearance||large colorless monoclinic needles|
|Melting point||75 °C (167 °F; 348 K)|
|Boiling point||220 °C (428 °F; 493 K) anhydrous at 130 ℃; decomposes at 220 ℃|
|26 g / 100 mL (0 ℃); 66 g / 100 mL (26 ℃)|
|Solubility in ethanol||insoluble|