Oxidation
an increase in oxidation number (aka: becomes less negative b/c of a loss of electrons)
Reduction
a decrease in oxidation number (aka: becomes more negative b/c of a gain in electrons)
Oxidizing Agents
-the ion or molecule that accepts the electrons
- this is the one that goes through reduction
Reducing Agents
-the ion or molecule that donates the electrons
-this is the one that goes through oxidation
Oxid. # of an element
when an element is the only one in a substance, such as Cl2 or P4, then the oxidation number is 0
Oxid. #s in monatomic ion
the oxidation number is equal to the charge of the ion
ex.in NaCl, Na+ has oxid. # of +1, and Cl- has oxid. # of -1
Elements With Constant Oxid. #
Hydrogen in compounds: +1
Oxygen in compounds: -2 (except in peroxide)
Group 1Metals =+1
Group 2 Elements=+2
Charge
charge of ions must add up to the overall charge of the ion or molecule