Redox Reaction Part 2

• In year 11, you're doing a lot of acid-base and redox reactions.
• Redox reactions involve the transfer of electrons, where one species is the oxidant and the other is the reductant.
• Add States to balance the charge.
• Balance the hydrogen atoms by adding H+ ions and then balance the charge by adding electrons.
• Balance the oxygen atoms by adding H2O to the opposite side.
• Balance the charge by adding electrons to the side with the increased charge.
• In a redox reaction, the oxidant causes oxidation of the other species but is itself self-produced.
• The reductant causes reduction and is itself oxidized.
• In redox reactions, the electrons lost by one species have to be gained by another, which is like the energy conservation principle.
• Oxidation States are a tool to keep track of how electrons are moving in a redox reaction.
• The oxidation states of free electrons are zero.
• The ion versions of elements have different oxidation states, such as chlorine ions and chloride ions, sodium ions, magnesium ions, nitrous ions, and so on.
• In compounds, the main group metals have the oxidation States equal to the charge of the iron, such as sodium which stays plus one, magnesium which stays plus two, hydrogen which is almost always plus one, and oxygen which is almost always negative two.
• The only occurrence where oxygen is not negative two in compounds is H2O2, which is hydrogen peroxide.
• Hydrogen peroxide, H2O2, was used during World War II and is a dangerous poison.
• The COS method, which stands for key atoms balance the oxygen atoms, is used to balance half equations.
• The sum of all oxidation states must equal the charge in the species.
• CO2 has a charge of zero and is neutral, therefore the other oxidation state needs to be equal to negative four.
• The charge of the species in a redox reaction determines whether or not it is redox.
• Oxygen is the reductant in a redox reaction where carbon is the only thing that is oxidized.
• In a combustion reaction, oxidation States change, and the individual atom values are used before the reaction.
• Redox reactions can be identified by determining whether or not the change in electrons is a movement or not.
• In a redox reaction, the reductant and the oxidant are identified.
• If oxidation state reduces and the species are reduced, the facilitation State increases, it has been oxidized.
• In the equation H2O2 plus one which makes this plus two overall and negative one, the individual atoms are plus one and negative one, with negative one instead of negative two.
• Hydrogen peroxide, H2O2, is a poison unless forced to by chemists.