= Solution
\b[Radiation changes the solution's chemistry by <radiolysis>; it does not turn Am(VI) nuclei into Am(V) nuclei.] An emitted alpha particle deposits energy into many water and solute molecules, generating ionized/excited species, hydrated electrons, <hydrogen> atoms and molecular products including <hydrogen peroxide>. Reducing products can supply the <electron> needed for
$$
\mathrm{AmO_2^{2+}+e^-\longrightarrow AmO_2^+}.
$$
For example, <hydrogen peroxide> can be oxidized while reducing two americyl(VI) ions:
$$
\mathrm{2AmO_2^{2+}+H_2O_2\longrightarrow2AmO_2^++O_2+2H^+}.
$$
The $0.3$ mM loss of Am(VI) equals the $0.3$ mM appearance of Am(V), preserving the measured dissolved <americium> total while transferring $0.3\,\mathrm{mmol\,L^{-1}}$ of <electron> equivalents. Oxidizing <radiolysis> products are also present, and the net reduction depends on acid, dissolved gases and scavengers; not every radiolytic event is reducing. In nitric acid, primary kinetic <work> identifies <hydrogen peroxide> and radiolytically produced <nitrous acid> as important reductants, with a rate controlled by total <americium> activity rather than necessarily by the instantaneous Am(VI) <concentration>.<Kinetics of the Autoreduction of Hexavalent Americium in Aqueous Nitric Acid by Travis S. Grimes and others>[2017, abstract: oxidation-state mass balance, UV–visible measurements and radiolytic reducing agents]{ref}
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