The objective of this research is to characterize monopropellant hydrazine based propellants which, by the use of ammonia and ammonia-water diluents, are capable of producing clean outlet gases in the temperature range of 175 to 2,200 F when passed through a catalytic decomposition chamber. During the report period thermochemical calculations were performed on a large number of cases involving various compositions of hydrazine, ammonia, and water. The effect of varying the amount of ammonia dissociation was investigated in the above calculations. The results are presented in this tabular and graphical form. Equipment was assembled for the preparation of solutions of hydrazine, ammonia, and water and for the measurement of vapor pressures and freezing points of these solutions.