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Neat droplets of O,O-diisopropylphosphorofluoridate (DFP) and O-1,2,2-trimethylpropyl methylphosphonofluoridate (Soman) decompose on glass. In thirty hours at room temperature over 40% of the Soman has been decomposed while nearly 15% of the DFP has been degraded. NMR spectroscopic analysis of the Soman showed that Soman decomposed exclusively by scission of the PF bond to form O-1,2,2-trimethylpropyl methylphosphonic acid. The rate of decomposition of the two organophosphorus fluorine substrates is proportional to the rate of hydrolysis. The results are consistent with earlier studies which showed that silica or magnesia promoted the decomposition of sarin (O-2-propylisopropyl methylphosphonofluoridate). The rate of decomposition on glass is accelerated in the presence of high humidity.

The syntheses of five new 4-alkyl-2-iodosobenzoic acids (3) are described. The iodine atom was introduced by ortho-directed lithiation of 4-alkylbenzyl alcohols followed by treatment with I 2 . The catalytic effectiveness of each of the products in the hydrolysis of 4-nitrophenyl diphenyl phosphate in microemulsions was studied. The 4-methyl- and 4-ethyl-substituted products were each found to be significantly better catalysts than the standard nonalkylated 2-iodosobenzoic acid (3, R = H). These results would indicate that microemulsions of these materials may find use in detoxification procedures

The kinetics of the dehydroxylation of talc have been measured in the temperature interval 1100–1160 K by means of isothermal weight-change determinations. The reaction follows first-order kinetics. Over the indicated temperature range the enthalpy of activation was found to be 101±4 kcal mol−1, and the entropy of activation was found to be 16±4 cal mol−1 K−1. The error estimates correspond to one standard deviation. The enthalpy necessary to break the MgOH bond was estimated from the heat of reaction for MgOH(g) → Mg(g)+OH(g). This turns out to be 97 kcal mol−1 in reasonable agreement with the measured enthalpy of activation. These activation parameters are consistent with the mechanism proposed for dehydroxylation of talc consisting of MgOH bond scission and subsequent migration of magnesium. These results contradict a previous report on the kinetics of talc dehydroxylation in which a diffusion-controlled expression was claimed to represent the rate of talc weight loss. It is suggested that the presence of adsorbed water on the talc used in the previous investigation is responsible for the discrepancy.

The burning rate of pressed strands made from a stoichiometric mix of magnesium and sodium nitrate was measured in nitrogen over the pressure range 0. 1 to 8.6 MPa. A plot of the logarithm of burning rate vs logarithm of pressure reveals two distinct regions with the 'slope break' occurring near 2 MPa. At the lower pressures, the slope is 0.3; at higher pressures, the slope is 0.05. The burning rate measured at 3.4 MPa was unchanged when oxygen replaced nitrogen; thus, gas-phase reactions do not affect the burning rate.