Numéro de référence
ISO 2485:1973
ISO 2485:1973
© ISO 2024
ISO 2485:1973
Sulfate de potassium à usage industriel — Dosage du potassium — Méthode gravimétrique à l'état de tétraphénylborate de potassium
Edition 1
1973-04
1973-04
Annulée
Résumé
Dissolution of a test portion taken from the laboratory sample, previosly ground and sifted. Addition of formaldehyde to transform any ammonium ions present into hexamethylenetetramine and of the disodium salt of ethylenediamin tetra-acetic acid to complex any extraneous cations present which could cause excessive errors. These additions have no detrimental effect on the precision or reproduciblility of the method. Precipitation of the potassium by sodium tetraphenylborate in a weakly alkaline medium. Drying and weighing of the precipitate.