Lanthanoids E-pH diagrams

Figure 18.6 depicts the E-pH diagram for Pu at 10 M. Again, there are notable resemblances to both U and Np, but evidence of a trend to lanthanoid resemblance is present. These include further stabilization of the An ion with an oxide PU2O3 making its appearance, and a decreasing stability of the Pu+ cation. 

As one moves through the actinoids, the trend toward lanthanoid characteristics becomes more evident with Am as Figure 18.7 (at 10 M) illustrates. A much larger area in the figure is occupied by the An ion, but resemblance to U, Np, and Pu remains in the upper regions of the E-pH diagram. 

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