Thermal Decomposition, Reaction with Oxygen, Reducing Properties

Thermal Decomposition, Reaction with Oxygen, Reducing Properties 

Phosphine decomposes only at higher temperatures. The thermal decomposition of phosphine under various conditions has been examined in detail. It is found to be a first order reaction. The rate constant for the decomposition of phosphine at 500 °C is approximately 8 10 sec 57,231-233) 

The thermal decomposition of phosphine on a glass surface can be satisfactorily described as a first order reaction using Eq. (13)  

The energies of activation of the decomposition on glass and silicon surfaces are 44.2 and 55.3 kcal/mol, respectively See also, 481-492) 

Phosphine-oxygen mixtures are relatively stable above the upper and below the lower critical explosion pressures. However, on irradiation with UV-light reaction occurs. It is assumed that the reaction is initiated by the photolytic dissociation of the PH3 molecule according to the equation  

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