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Potassium tartrate, dipotassium tartrate or argol has formula K2C4H4O6.
P 2522 (OTTO) Potassium tartrate, GR 98%+ Cas 921-53-9 - used to prepare microorganism culture medium. P 2522 (OTTO) Potassium tartrate, GR 98%+ Cas 921-53-9 - used as a buffering agent.