FOURIER-TRANSFORM IR SPECTROSCOPIC DETERMINATION OF THE EQUILIBRIUM-CONSTANT FOR H2O-CL2O-REVERSIBLE-2HOCL

Using the Fourier transform infrared method, the equilibrium constant Keq for H2O + Cl2O = 2HOCl has been determined to be (6.8 ± 1.0) × 10-2 at 295 = 3 K under relatively dry conditions [P(H2O) < 10 Torr]. From the hydrogen mass balance for the thermal reaction HCl + Cl2O - HOCl + Cl2, the integrated band intensities for ν2 (≈ 1240 cm-1) and ν3 (≈ 740 cm-1) of HOCl are 265 and 45 cm-2 atm-1 ± 5%, respectively. The present value of Keq gives estimates of ΔH0 f and ΔG0 t of -17.9 and -14.9 kcal mole-1 for HOCl. At P(H2O) > 10 Torr, additional absorption bands centered at 785 and 3450 cm-1 were observed due presumably to the formation of an HOCl - H2O adduct. © 1979.