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Last Update: 08/22/2024 06:07 AM
Current Deck: Chem Unit 3 T1 Chemical Equilirbium Systems::U3 T2 Redox Reactions
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Commit #132593
What are the oxidation number/state rules
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Commit #132593
1. Elements: Substances in their elemental form have an oxidation state of 0 (i.e. Mg is 0/ Cl2 is 0 as these are the pure forms found in nature)
2. Ions: The charge on the ion is the oxidation number/state of the ion (i.e. Mg2+ is +2/ Cl- is -1)
3. Oxygen: has an oxidation number/state of -2 when in compound, except in peroxides where the oxidation number/state is -1 (i.e. in H2O, O is -2 but in H2O2 (hydrogen peroxide), O is -1)
4. Hydrogen: has an oxidation number/state of +1 in compount, except in compound with metals where oxidation number/state is -1 (i.e. in CH4, H is +1 but in NaH, H is -1)
5. Metals: in group 1,2,13 have their respective oxidation number/state where group 1 is +1, group 2 is +2 and group 13 is +13 as it is the number of electrons required to be lost to form stable valence shell
6. Molecular ions and molecules: the sum of oxidation states is equal to the charge on the molecular ion, while the sum is equal to 0 for molecules; the most electronegative element takes the negative oxidation number
i.e.
2. Ions: The charge on the ion is the oxidation number/state of the ion (i.e. Mg2+ is +2/ Cl- is -1)
3. Oxygen: has an oxidation number/state of -2 when in compound, except in peroxides where the oxidation number/state is -1 (i.e. in H2O, O is -2 but in H2O2 (hydrogen peroxide), O is -1)
4. Hydrogen: has an oxidation number/state of +1 in compount, except in compound with metals where oxidation number/state is -1 (i.e. in CH4, H is +1 but in NaH, H is -1)
5. Metals: in group 1,2,13 have their respective oxidation number/state where group 1 is +1, group 2 is +2 and group 13 is +13 as it is the number of electrons required to be lost to form stable valence shell
6. Molecular ions and molecules: the sum of oxidation states is equal to the charge on the molecular ion, while the sum is equal to 0 for molecules; the most electronegative element takes the negative oxidation number
i.e.