Liquid monopropellant

A liquid monopropellant having (1) from about 10 to about 80 weight percent of an substituted ammonium nitrate which is methylammonium nitrate, dimethylammonium nitrate, trimethylammonium nitrate, ethylammonium nitrate, diethylammonium nitrate, n-propylammonium nitrate, isopropylammonium nitrate, ethanolammonium nitrate, diethanolammonium nitrate, triethanolammonium nitrate, or mixtures thereof, (2) from about 5 to about 60 weight percent of ammonium nitrate, and (3) from about 5 to about 50 weight percent of water. A second embodiment of this invention is a monopropellant in which ammonium nitrate is omitted and from about 60 to about 95 weight percent of the substituted ammonium nitrate and from about 5 to about 40 weight percent of water is used.