The Mass-Spectrometric Analysis of Oxygen in Carbon Monoxide and Carbon Dioxide

Abstract

Results of measurements of oxygen-18 abundances in carbon monoxide and carbon dioxide using a Nier-type isotope-ratio mass spectrometer are given. Carbon monoxide is a far superior gas to carbon dioxide as a carrier for the oxygen isotopes because of the more rapid pump-out and almost complete absence of memory in the mass spectrometer. The slight variation of the measured ratio with output voltage is attributed mainly to the non-ohmic response of the grid resistors to the electrometer valves.