1. Oxidation Reduction Reactions

2. Types of Reaction  Oxidation-Reduction called Redox Ionic compounds are formed through the transfer of electrons. An Oxidation-reduction reaction involves the transfer of electrons. We need a way of keeping track.

3. Oxidation States A way of keeping track of the electrons. need the rules for assigning (memorize).  The oxidation state of elements in their standard states is zero.  Oxidation state for monoatomic ions are the same as their charge.

4. Oxidation states  Oxygen is assigned an oxidation state of -2 in its covalent compounds except as a peroxide.  In compounds with nonmetals hydrogen is assigned the oxidation state +1.  In its compounds fluorine is always –1. The sum of the oxidation states must be zero in compounds or equal the charge of the ion.

5. Oxidation States Assign the oxidation states to each element in the following. CO 2 NO 3 - H 2 SO 4 Fe 2 O 3 Fe 3 O 4

6. Oxidation-Reduction Oxidation means an increase in oxidation state - lose electrons. Reduction means a decrease in oxidation state - gain electrons. The substance that is oxidized is called the reducing agent. The substance that is reduced is called the oxidizing agent. OIL RIG LEO GER

7. Identify the Label the following: Oxidizing agent Reducing agent Substance oxidized Substance reduced Fe (s) + O 2 (g)  Fe 2 O 3 (s) SO 3 - + H + + MnO 4 -  SO 4 - + H 2 O + Mn +2

8. Half-Reactions All redox reactions can be thought of as happening in two halves. One produces electrons - Oxidation half. The other requires electrons - Reduction half.

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