Abstract: | The equilibrium I2(g) + 2NO(g) = 2INO(g) has been studied at room temperature by ultraviolet absorption spectroscopy. The equilibrium constant has been measured as Kp = (2.7 ± 0.3) × 10?6 atm?1 at 298 K. Third-law calculations lead to ΔH°f,298 (INO) = 120.0 ± 0.3 kJ/mol. The relative absorption spectrum of INO has been measured between 225 and 300 nm. Quantitative measurements gave ?(λmax = 238 nm) = (1.79 ± 0.5) × 104 L/mol·cm and ?(410 nm) = 234.7 ± 21 L/mol·cm. |