| what is oxidation? | the loss of electrons by a reactant in any reaction |
| what is reduction? | the gain of the electrons by a reactant in any reaction |
| what are the steps in writing balanced ion-electron equations for reactions not found in your data booklet? | balance oxygen atoms with water molecules
balance hydrogen atoms with hydrogen ions
balance the charges with electrons |
| write out the balanced ion electron equation for
MnO4- (aq) → Mn2+ (aq) | Balance any oxygen atoms with water molecules
MnO4- (aq) → Mn2+ (aq) + 4H2O (l)
Balance any H atoms with H+(aq) ions
MnO4- (aq) + 8H+ (aq) → Mn2+ (aq) + 4H2O (l)
Balance the charges with electrons
MnO4- (aq) + 8H+ (aq) + 5e- → Mn2+ (aq) + 4H2O (l) |
| how can you tell if a reaction is a redox reaction? | reaction involves metal atoms as a reactant or a product
reaction involves molecules and ions of the same non-metal
reaction involves a metal ion with two different charges
sulfate reacting to form sulfite and vice versa |
| in redox reactions, what type of ions are sodium and potassium? | spectator ions |
| are neutralisation reactions redox reactions? | no |
| are precipitation reactions redox reactions? | no |
| what is an oxidising agent | a substance which accepts electrons during a chemical reaction (it is reduced) |
| what is a reducing agent | a substance which donates/loses electrons during a chemical reaction (it is oxidised) |
| do elements with low electronegativities act as reducing or oxidising agents? | reducing agents as they tend to form ions by losing electrons |
| do elements with high electronegativities act as reducing or oxidising agents? | oxidising agents as they tend to form ions by gaining electrons |
| where are the strongest oxidising and reducing agents found on the periodic table? | strongest reducing agents are in group 1
strongest oxidising agents are in group 7 |
| where are the strongest oxidising and reducing agents found on the electrochemical series? | strongest oxidising agents: bottom left corner
strongest reducing agents: top right corner |
| what is a practical use of oxidising agents | they can kill bacteria and fungi and inactivate viruses |
| why are oxidising agents ideal for use as bleach for clothes and hair? | the oxidation process is an effective means of breaking down coloured compounds |
| name a practical use of hydrogen peroxide | an oxidising agent that can be used to bleach hair, teeth, cotton, wool and paper |
| name a practical use of dichromate and permanganate ions | they are group ions that are strong oxidising agents in acidic solutions used to treat skin infections used to keep water in fish tanks and ponds free from fungi and bacteria |
| what is a practical use of iodine as an oxidising agent? | can be used to treat burns or wounds by keeping them free of infections |
| what is a use of carbon monoxide? | reducing agent can extract some metals from their ores |
