The Accommodation Coefficients of Carbon Monoxide, Oxygen, and Carbon Dioxide on Platinum in the Mixture of the Gases

Abstract

For the purpoSe of studying the energy transfer between gas molecules and a solid surface in a mixture of gases, the heat loss from a piatinum ribbon was measured in the mixture of carbon monoxide, oxygen, and carbon dioxide under the pressure range of IAv4 10 2 mmHg. and at ribbon temperatures of 165 and 2280C. The heat loss in the mixed gas was found to be the sum of the heat losses measured separately for each gas. The result was explained as follows. ln the gas mixture, the surface of platinum was covered almost completely with a chemisorbed layer of carbon monoxide, and the impinging gas melecules were adsorbed physically on the layer and exchanged their energy with it. For carbon monoxide, the energy transfer and the accommodation coefficient in the rnixture should be identica1 to what in carben monoxide alone. Therefore, the additivity of the heat loss observed in this Study shows that the accommodation coeMcients of oxygen and arbon dioxide in the mixture were equal to those observed separately in each gas.