Thermodynamic properties of ammonia as an ideal gas

Abstract

Thermodynamic functions for ammonia as an ideal gas at one atmosphere pressure have been evaluated. The contribution of the highly anharmonic out-of-plane vibrational mode, including its large coupling with rotation and its coupling with the other vibrational modes, is considered in detail. Tables of C P ° / R , ( H ° - E 0 ° ) / R T , ( E 0 ° - G ° ) / R T , and S°/R have been calculated at closely spaced intervals from 50 to 5000 °K within an overall uncertainty of less than 0.1 percent at 1000 °K.