Heat of Formation and Entropy of Titanium Tetrachloride from an Investigation of the Equilibrium: TiO2(s)+4HCl(g) = TiCl4(g)+2H3O(g)

Abstract

The equilibrium, TiO₂(rutile)+4HCl=TiCl₄(g)+2H₂O(g), was studied in the temperature range of 800—1400°K by means of a flow method in which HCl was passed over a sample of rutile. The heat of reaction was found to be 12.9 kcal/mole in this temperature range. This leads to a value of —182.9±0.5 kcal/mole for ΔH_f of TiCl₄(g) and —192.5±0.5 kcal/mole for ΔH_f of TiCl₄(l). The entropy of TiCl₄(g) at 1100°K is found to be 124 cal/°/mole.