You wish to prepare approximately 50 g of a Y2O3stabilized Z

You wish to prepare approximately 50 g of a Y₂O₃-stabilized ZrO₂ powder containing 8 mol% Y₂O₃ by the process of co-precipitation from solution. You start by dissolving ZrOCl₂.8H₂O and YCl₃.6H₂O in 300 cm³ of deionized water and add the solution drop-wise into a stirred, excess solution of NH₄OH prepared by diluting a concentrated NH₄OH solution containing 30 wt% NH₃. Determine the amount of each starting material and the volume of each solution required for the process, assuming that the reaction goes to completion.

Solution

To get 50 g of Y2O3 stabilized ZrO2

Y2O3 = 8 mol%

          = 0.08 x 225.81

          = 18.0648 g

ZrO2 = 50 - 18.0648

         = 31.9352 g

To get 31.9352 g ZrO2, we would start with = 322.252 x 31.9352/123.22

                                                                      = 83.52 g of ZrOCl2.8H2O in 300 ml water

To get 18.0648 g Y2O3, we would start with = 303.3565 x 2 x 18.0648/225.81

                                                                       = 48.54 g of YCl3.6H2O in 300 ml water