Ceriometry

a titrimetric method for the determination of reducing agents using standard solutions of Ce(IV) compounds, for example, (NH₄)₂[Ce(SO₄)₃]. The analysis is carried out in an acid medium. The titration end point is established visually using chemical indicators, potentiometrically, or by other methods.

Ceriometry is used for the determination of Sb(III), As(III), Fe(II), Mo(V), nitrogen-containing compounds, such as hydroxylamine and nitrites, phosphorus-containing compounds, such as hypophosphites and phosphites, and oxalic acid, hydroquinone, and hydroxy acids. It has several advantages over other methods. For example, ceriometry is superior to permanganate titration, since solutions of Ce(IV) compounds are stable and the titration is not disturbed by chloride ions.