Iron metal reacts with oxygen to produce iron(III) oxide (rust)
Write a word equation and a chemical equation for this process
Iron + oxygen Iron(III) oxide
This is an example of a REDOX reaction
Writing ion-electron equation practice: Sodium atoms losing electrons to form sodium ions Sulphur atoms gaining electrons to become sulphur ions Copper(II) ions being reduced Bromine atoms being reduced Fe + O 2 Fe 2 O 3
Write an ion-electron equation to show the rusting of iron.
A cell is made using an iron nail and a carbon rod, in a solution of ferroxyl indicator. Decide which statements are true:
SG textbook, p118-119
A Iron Carbon Electrons move from the carbon rod to the iron Electrons flow through the solution A blue colour appears at the iron electrode The mass of the iron electrode decreases The iron is oxidised Set up an experiment to answer the above questions.
There are two types of way to help prevent corrosion:
Stops oxygen and water coming into contact with the metal:
Oil or grease
Tin plating – covering in molten tin
Galvanising – covering in molten zinc (more expensive)
Carry out electroplating practical (7.2)
ELECTROPLATING Copper Gold Gold ions, Au + DC -ve +ve The metal to be coated is at the NEGATIVE terminal POSITIVE ions of the OTHER METAL are in the solution These ions are attracted to the negative terminal, and when they meet it turn into atoms So the copper is coated in gold atoms Write an ion-electron equation for the reaction occurring at the negative electrode Is this oxidation or reduction? Check-test 12.2 ext.
A Iron Magnesium A metal high in the electrochemical series is connected to the metal to be protected and is sacrificed - This is used in underground pipes Mg In terms of electrons, explain how sacrificial protection works.