Automatic analysis of alkali metals halides etc. by means of the use of ion-selective electrodes

A method for determining ions in a continuously flowing liquid stream consisting essentially of a liquid sample solution in a liquid carrier comprising providing a measuring cell and an ion-selective electrode, said ion-selective electrode having a sensitive surface located in the measuring cell, freely and continuously flowing the liquid stream downwardly over the sensitive surface of the ion-selective electrode in a form of a thin, continuous sheet wherein one side of the liquid sheet is in contact with the sensitive surface of the ion-selective electrode as the sheet flows across the sensitive surface while the other side of the liquid sheet is exposed to the atmosphere of the measuring cell, the pressure of which is the same as the atmospheric pressure outside the cell, immediately thereafter permitting the liquid stream to flow as the same continuous sheet without interruption into a reservoir in the measuring cell consisting essentially of the liquid carrier and in which a reference electrode is placed, said ion-selective electrode being located above the liquid level in the reservoir, so that the potential difference between the electrodes in the measuring cell can be continuously determined.