摘要:

Oxygen chemisorbed on activated cocoanut charcoal at 20 °C. was found to exert no measurable equilibrium pressure. The small residual pressures obtained under experimental conditions were shown to be due to the presence of slight impurities in the oxygen employed. The impurities responsible for these residual pressures were largely nitrogen and accompanying rare gases.The velocity of chemisorption of oxygen decreased rapidly with increase in its concentration on the charcoal, approaching a limiting zero velocity at a concentration of 84 × 10−6 moles per gm. This coincides with the concentration at which the heat of adsorption drops rapidly to the limiting value obtained for physical adsorption.After this limiting concentration was reached, adsorbed oxygen showed true equilibrium with the gas phase. For small additional increases in concentration, the equilibrium pressure was found to increase as a linear function of the concentration, with a proportionality constant of 0.276 mm. per micromole. This represents physical adsorption as compared to chemisorption for lower oxygen concentrations.

ISSN:1923-4287    

DOI:10.1139/cjr40b-004

出版商:NRC Research Press    

年代:1940

数据来源: NRC

摘要:

An investigation has been made of the quenching of mercury resonance radiation (λ2537) by ethylene. A quenching cross-section of 48 ± 5 × 10−16 cm.2was found.

ISSN:1923-4287    

DOI:10.1139/cjr40b-005

出版商:NRC Research Press    

年代:1940

数据来源: NRC

摘要:

An investigation has been made of the cadmium photosensitized reactions of ethylene and of ethylene-hydrogen mixtures. With ethylene alone the quantum yield of the reaction is very low, viz., about 0.01. With ethylene-hydrogen mixtures the quantum yield is about 0.5 to 0.7 depending upon the conditions. The products of the reaction are methane, ethane, propane, butane, propylene, and higher hydrocarbons. The mechanism of the reaction is discussed and compared with that of the mercury photosensitized reaction. It is concluded that the main steps of the reaction in the presence of hydrogen aretogether with radical recombination reactions, and reactions of the type

ISSN:1923-4287    

DOI:10.1139/cjr40b-006

出版商:NRC Research Press    

年代:1940

数据来源: NRC

摘要:

The density of gaseous chlorine has been determined over the temperature range 15° to 75 °C. and up to two atmospheres. The values obtained are compared with those extant in the literature, and excellent agreement is found with the very precise measurements of Jaquerod and Tourpaian at 15 °C. and 725 mm. pressure. There is also good agreement, over the temperature range of this investigation, with the measurements of Pier at a pressure of one atmosphere. The equation of state proposed by Maass and Mennie is shown to fit the experimental results over the whole range and to give, for temperatures and pressures outside the region covered by this investigation, values of the density of gaseous chlorine that are in good agreement with the results obtained by Jaquerod and Tourpaian, and by Pier. Tables of calculated and experimentally determined densities and apparent molecular weights show the deviations of gaseous chlorine from ideality. The equation of state is given in a convenient form for the calculation of the density of the gas in industrial applications.

ISSN:1923-4287    

DOI:10.1139/cjr40b-007

出版商:NRC Research Press    

年代:1940

数据来源: NRC

摘要:

An attempt has been made to determine the exact composition of the first crystals that separate out on freezing solutions of hydrogen peroxide and water of various concentrations. Special care was taken to ensure complete removal of any liquid wetting the solid phase. In all cases the crystals were found to contain both components and in proportions usually different from those in the mother-liquor. Owing to the limitations of the experimental method used, the results are only approximate, but they afford ample evidence for the existence of solid solutions. The possibility of hydrogen peroxide forming solid solutions with water is discussed from the standpoint of the crystal structure of both components.

ISSN:1923-4287    

DOI:10.1139/cjr40b-008

出版商:NRC Research Press    

年代:1940

数据来源: NRC