Vapor pressures and liquid densities for ammonium iodide (NH(4)I) + ammonia (NH(3)) mixtures were measured over a wide range of temperatures and molalities Vapor pressures of the NH(4)I + NH(3) mixtures were measured at temperatures ranging from (303.12 to 373 16) K and molalities ranging up to 19.314 mol . kg(-1) of NH(4)I Vapor pressures were measured with a static method The experimental values were correlated with Antoine's equation Liquid densities of the NH(4)I + NH(3) mixtures were measured at temperatures ranging from (303.15 to 373.15) K. pressure ranging from (10 0 to 30 0) MPa, and monthlies ranging up to 16 465 mol . kg(-1) of NH(4)I Liquid densities were measured with a piezometer The experimental values were correlated with a Tait form equation.