GAS-SENSITIVE CELL TO DETERMINE AMMONIA-ION Russian patent published in 2001 - IPC

FIELD: analytical chemistry, ionometric methods of analysis. SUBSTANCE: invention is intended to detect volatile components in gas phase. Proposed gas-sensitive cell presents vessel with analyzed solution separated by air space from electrode system. Electrode system closes vessel air-tight and is made of indicating ammonia-selective electrode and portion of salt bridge in the form of tube ending with side capillary. Another portion of salt bridge coming in the form of 150-200 ml vessel contains silver chloride comparison electrode and is brought out of limits of vessel. Electrodes contact through hanging drop of electrolyte on surface of ammonia-selective electrode and side capillary of salt bridge. Alkali to form ammonia is supplied into closed cell through needle of syringe. Organic buffer solution of tris(oxymethyl)aminomethane is chosen in the capacity of electrolyte in hanging drop and in connecting bridge. EFFECT: prolonged service life of cell and raised selectivity of determination of ammonia-ion. 2 cl, 1 dwg, 1 tbl