[Answer] Which rule for assigning oxidation numbers is correct?

Answer: Oxygen is usually -2.

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Which rule for assigning oxidation numbers is correct? Fri Feb 08 2002 13:30:00 GMT-0500 (Eastern Standard Time) · This approach yields correct oxidation states in oxides and hydroxides of any single element and in acids such as H 2 SO 4 or H 2 Cr 2 O 7. Its coverage can be extended either by a list of exceptions or by assigning priority to the postulates. The latter works for H 2 O 2 where the priority of rule 1 leaves both oxygens with oxidation state −1. Stock nomenclature for inorganic compounds is based on the indication of the oxidation number (as a roman numeral in parentheses) of each of the major elements in the compound e.g. iron(III) chloride. It is widely if sometimes incorrectly used on Wikipedia for the titles of articles about inorganic compounds. Sun Aug 05 2001 14:30:00 GMT-0400 (Eastern Daylight Time) · The Cahn–Ingold–Prelog (CIP) sequence rules named for organic chemists Robert Sidney Cahn Christopher Kelk Ingold and Vladimir Prelog — alternatively termed the CIP priority rules system or conventions — are a standard process used in organic chemistry to completely and unequivocally name a stereoisomer of a molecule.: 26 The purpose of the CIP system is to assign an … General rule . From Wikipedia:Naming ... is assigned its oxidation number . Except in rare cases (none at present) we do not assign the oxidation number in the anion: hence potassium permanganate ... ignoring any prefixes and numbers . Correct article names and first words in sentences are: 1 1 1-Trichloroethane not 1 1 1-trichloroethane; Fractional oxidation numbers . What about superoxides? According to my textbook (Oxtoby) oxygen can have an oxidation number of -1/2 - Reddaly. That's because you have two different oxygen atoms: one with oxidation number zero and one with oxidation number -...

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