It is crucial in understanding the nature of various reactions. Would you like to write for us? Well, we're looking for good writers who want to spread the word. Get in touch with us and we'll talk
Oxidation states of carbon
Rules for Assigning Oxidation Numbers
Oxidation state indicates the degree of oxidation for an atom in a chemical compound; it is the hypothetical charge that an atom would have if all bonds to atoms of different elements were completely ionic. Oxidation states are typically represented by integers, which can be positive, negative, or zero. Generally, the oxidation state for most common elements can be determined from their group number on the periodic table. This is summarized in the following chart:. Keep in mind that oxidation states can change, and this prediction method should only be used as a general guideline; for example, transition metals do not adhere to any fixed rules and tend to exhibit a wide range of oxidation states.
Assigning Oxidation States Example Problem
The donation of electrons is called the oxidation and the gain of electrons is called the reduction. The oxidation state of an atom in its free or ground state is taken as zero. When the atom loses electrons its oxidation state increases and when the atom gains electrons its oxidation state decreases. The term oxidation-number represents the positive or negative character of the atom in a compound.
The term oxidation was first used to describe reactions in which metals react with oxygen in air to produce metal oxides. When iron is exposed to air in the presence of water, for example, the iron turns to rust—an iron oxide. When exposed to air, aluminum metal develops a continuous, coherent, transparent layer of aluminum oxide on its surface.