25.00 cm³ of a solution X containing 21.4 g U(VI) dm⁻³ was reduced with Zn amalgam, decanted from the amalgam, and after being aerated for 5 min, was titrated with 0.1200moldm⁻³ Ce(IV) solution; 37.5cm³ of the latter was required for reoxidation of the uranium to U(VI). Solution X (100cm³) was then reduced and aerated as before, and treated with an excess of dilute aqueous KF. The resulting precipitate (after drying at 570 K) weighed 2.826 g. Dry O₂ was passed over the precipitate at 1070 K, after which the solid product weighed 1.386 g. This product was dissolved in water, the fluoride in the solution precipitated as PbClF, 2.355 g being obtained. Deduce what you can concerning the chemical changes in these experiments.