(1-Hydroxyethylidene)bisphosphonic acid, sodium salt 1-Hydroxyethanediphosphonic acid, sodium salt 29329-71-3 EINECS 249-559-4 Hydroxyethylidene diphosphonic acid, sodium salt Phosphonic acid, (1-hydroxyethylidene)bis-, sodium salt Phosphonic acid, (1-hydroxyethylidene)di-, sodium salt