(1-Hydroxyethylidene)diphosphonic acid, tetrapotassium salt 14860-53-8 2809-21-4 DIPHOSPHONIC ACID, (1-HYDROXYETHYLIDENE)-, TETRAPOTASSIUM SALT EINECS 238-928-5 Ethane-1-hydroxy-1,1-diphosphonic acid, tetrapotassium salt Phosphonic acid, (1-hydroxyethylidene)bis-, tetrapotassium salt Tetrapotassium (1-hydroxyethylidene)bisphosphonate Tetrapotassium etidronate