No abstract

Investigations of the reaction of sodium chloride particles with 0.1-1.5% mixtures of nitrogen dioxide and sulfur dioxide in air showed that nitrogen dioxide reacted with sodium chloride to form nitrosyl chloride (NOCI), a corrosive gas. The reaction was rapid but surface area dependent. It proceeded equally on dry or moist particles. Free energy calculations indicate a favorable free energy change and a large equilibrium constant. It is suggested that this reaction is of importance in studying the chemical and physical interactions of halide aerosols in an atmosphere containing nitrogen dioxide.

No abstract

drops of concentrated sulfuric acid and 10 ml. of hydrofluoric acid (48%). This is heated until dry, ignited, cooled, and weighed. The difference in weight represents silica.Any residue left in the platinum crucible is fused with potassium acid sulfate, the mass dissolved in hydrochloric or sulfuric acid (1 to 9), and the contents are added to the combined original filtrates which should have a total acidity of 10 to 20% and a total volume of not more than 250 ml. The required amount of halomandelic acid is now added and the zirconium content of the sample determined as described above.Results obtained by this procedure are given in Table III. SUMMARY Zirconium in aluminum alloys can rapidly and conveniently be 'determined gravimetricaliy by the mandelate method. The use of p-chloroor p-bromomandelic acid is preferred to mandelic acid (4). No significant difference exists between the chloro and bromo derivative. These reagents are now available com-mercially from the H.

Xi Qi- (8) with terms containing two (or more) rate constants as factors. A calculation to the second approximation is given in a previous paper (3). APPLICATIONSThe method described above is of special value for the analysis of a solution containing a number of solutes which fulfill the following conditions:All solutes must contain the same tracer isotope, which must be in radioactive equilibrium with respect to the different solutes.A solvent must be found, into which Qi