Oxidation and Reduction

Oxidation and Reduction

1. Oxidation numbers

   • Oxidation is an increase in oxidation number, Reduction is a decrease in oxidation number
   • Uncombined elements = 0
   • Neutral compounds = 0
   • Ion = charge on ion
   • The most electronegative element in compound is negative.
   • Oxygen = -2
     • Hydrogen = +1
       • Fluorine = -1
         • Chlorine = -1
   • Group 1 metals = +1
     • Group 2 metals = +2

2. Oxidation is loss of electrons.

   • Oxidation is gain of oxygen

3. Reduction is gain of electrons.

   • Reduction is loss of oxygen

4. Oxidising agent - something that oxidises something else.

   • Reducing agent - something that reduces something else.