Original sentence: At atmospheric pressure TiI4 melts at 150oC and boils at 377oC, while ZrI4 melts at 499oC and boils at 600oC.Impure titanium, zirconium, hafnium, vanadium, thorium or protactinium is heated in an evacuated vessel with iodine at 50-250oC.The gaseous metal tetraiodide is decomposed on a white hot tungsten filament (1400oC)
Edited sentence: At atmospheric pressure TiI4 melts at 150 °C and boils at 377 °C, while ZrI4 melts at 499 °C and boils at 600 °C.Impure titanium, zirconium, hafnium, vanadium, thorium or protactinium is heated in an evacuated vessel with iodine at 50–250 °C.The gaseous metal tetraiodide is decomposed on a white hot tungsten filament (1400 °C)