Editing OxidationNumber
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<center><b>Rules for Assigning Oxidation Number</b></center><br> <br> 1. The oxidation number of any element in its elemental form is zero.<br> 2. The oxidation number of any monoatomic ion is the same as its charge<br> 3. All Group 1 elements (Alkali metals), except hydrogen, have an oxidation number of +1.<br> 4. All Group 2 elements (Alkaline Earth metals) have an oxidation number of +2.<br> 5. Fluorine always has an oxidation number of -1 in its compounds.<br> 6. Oxygen has an oxidation number of -2 except as a peroxide (i.e. sodium peroxide, Na<sub>2</sub>O<sub>2</sub>)<br> 7. Hydrogen has an oxidation number of +1 except in metal hydrides (i.e. sodium hydride, <nowiki>NaH</nowiki>)<br> 8. The more electronegative elements always have the negative oxidation number and use the column "charge" as the number value (i.e. <nowiki>CO</nowiki>, O<sup>-2</sup>, C<sup>+2</sup> since O is more electronegative than C)<br> 9. The algebraic sum of all the oxidation numbers of all the atoms in a neutral compound is zero.<br> 10. For polyatomic ions, the algebraic sum of the oxidation numbers of all the atoms in the ion must equal the ion's charge.<br> <br> Table for Electronegativity values can be found at ElectronegativityTable. <b>Everybody must use only this table.</b><br> <br> <b>Example - What is the oxidation number of C and N in cyanide ion?</b><br> CN<sup>1-</sup><br> a. Use Rule #8 and #10<br> b. N is more electronegative than C so N has the negative oxidation number.<br> c. N is in the third column over from Noble Gas so it has an oxidation number of -3<br> d. Using Rule 10, C must be +2.<br> <br> <br>
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