Zirconium perchlorate as cold as possible. Zirconium perchlorate is very hydroscopic forming hydrates, and it is hydrolysed by water to yield zirconyl perchlorate, ZrO(ClO). Zirconium perchlorate reacts with vaseline, methyl nitrate or acetonitrile. Zirconium perchlorate is inert towards carbon tetrachloride, chloroform, and dimethylformamide. Zirconium perchlorate reacts with benzene at 20°C, but at -10°C crystals of Zr(ClO)•CH are deposited. Zirconium perchlorate has solid state transition around 45°C, a melting point between 95.5 and 96.0°C and a decomposition point starting around 120°C. The zirconyl perchlorate formed in the heat decomposition, itself decomposes around 290°C to form zirconia, chlorine and oxygen. In the gas phase
Zirconium dioxide the basis for the purification of zirconium metal and is analogous to the Kroll process. Zirconium dioxide is one of the most studied ceramic materials. ZrO adopts a monoclinic crystal structure at room temperature and transitions to tetragonal and cubic at higher temperatures. The change of volume caused by the structure transitions from tetragonal to monoclinic to cubic induces large stresses, causing it to crack upon cooling from high temperatures. When the zirconia is blended with some other oxides, the tetragonal and/or cubic phases are stabilized. Effective dopants include magnesium oxide (MgO), yttrium oxide (YO, yttria), calcium oxide (CaO), and