Oxidation is the addition of oxygen, removal of hydrogen, the loss of electrons or the increase in oxidation number.
Reduction is the removal of oxygen, addition of hydrogen, the gain of electrons or the decrease in oxidation number.
The oxidation number can be used to check that all the electrons in a formula or reaction can be accounted for.
Reduction is the removal of oxygen, addition of hydrogen, the gain of electrons or the decrease in oxidation number.
The oxidation number of an element is the number of electrons involved in its bonding to another element.
The oxidation number can be used to check that all the electrons in a formula or reaction can be accounted for.
| The oxidation number for uncombined elements is zero and for an ion is the charge of the ion. | The sum of the oxidation numbers is equal to the total charge which is zero in neutral compounds. | The more electronegative element is given a negative oxidation number. | Fluorine is always -1, hydrogen +1 except with a less electronegative element. | Oxygen is -2 except in peroxides where it is -1 and with fluorine where it is positive. | Roman numerals are used for ions with different charges e.g. iron(II) Fe2+ and iron (III) Fe3+. |