Editing Ceric ammonium nitrate (section)

==Preparation, properties, and structure==
The [[anion]] {{chem2|[Ce(NO3)6](2-)}} is generated by dissolving [[cerium(III) oxide|{{chem2|Ce2O3}}]] in hot and concentrated [[nitric acid]] ({{chem2|HNO3}}).<ref>{{Cite journal |last=Smith |first=G.Frederick |date=June 1963 |title=An improved preparation of ammonium hexanitratocerate(IV) and routine analytical testing procedure to prove primary reference standard purity |url=https://linkinghub.elsevier.com/retrieve/pii/0039914063800934 |journal=Talanta |language=en |volume=10 |issue=6 |pages=709–710 |doi=10.1016/0039-9140(63)80093-4|url-access=subscription }}</ref>

The salt consists of the hexanitratocerate(IV) anion {{chem2|[Ce(NO3)6](2-)}} and a pair of [[ammonium]] cations {{chem2|NH4+}}. The ammonium ions are not involved in the oxidising reactions of this salt. In the anion each nitrate group [[chelate]]s the cerium atom in a [[bidentate]] manner as shown below:

{{multiple image
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 | total_width = 400
 | image1 = Hexanitratocerat.svg
 | caption1 = Hexanitratocerate anion
 | image2 = Hexanitratocerate(IV)-ion-from-CAN-xtal-3D-bs-17.png
 | caption2 = [[Ball-and-stick model]]<ref>{{Cite journal | url = https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1598999&DatabaseToSearch=Published | title = CSD Entry 1598999, ICSD Entry 22219, H<sub>8</sub>CeN<sub>8</sub>O<sub>18</sub> | website = [[Cambridge Structural Database]]: Access Structures | publisher = [[Cambridge Crystallographic Data Centre]] | access-date = 2021-11-05}}</ref><ref name="Beineke&Delgaudio"/>
}}

The anion {{chem2|[Ce(NO3)6](2-)}} has T<sub>h</sub> (idealized O<sub>h</sub>) [[molecular symmetry]]. The {{chem2|CeO12}} core defines an [[icosahedron]].<ref name="Beineke&Delgaudio">{{cite journal | author = Thomas A. Beineke | author2 = J. Delgaudio | year = 1968 | title = Crystal structure of ceric ammonium nitrate | journal = Inorg. Chem. | volume = 7 | issue = 4 | pages = 715–721 | doi = 10.1021/ic50062a020 | osti = 4799348 }}</ref>

{{chem2|Ce(4+)}} is a strong one-electron [[oxidizing agent]]. In terms of its redox potential ({{nowrap|''E''° ≈ 1.61 V}} vs. [[Normal hydrogen electrode|N.H.E.]]) it is an even stronger oxidizing agent than [[Chlorine|{{chem2|Cl2}}]] ({{nowrap|''E''° ≈ 1.36 V}}). Few shelf-stable reagents are stronger oxidants. In the redox process Ce(IV) is converted to Ce(III), a one-electron change, signaled by the fading of the solution color from orange to a pale yellow (providing that the substrate and product are not strongly colored).