Rusting Flashcards
What is rusting?
specific corrosion of iron when reacting with oxygen and water
What is the word equation for rusting?
iron + oxygen + water -> hydrated (iii) oxide
What is the chemical name for rust?
hydrated iron (iii) oxide
What are the types of rust prevention methods?
barrier methods, galvanising, sacrificial protection
What are barrier methods?
creating a physical barrier to environment so oxygen and water cannot be exposed to the metal and cause rusting.
What are the types of barrier methods?
painting, oiling, plastic
What is galvanising?
coating iron with zinc since it is more reactive and it will create ZnCO3 coating (after reacting with oxygen and co2 from air) which protects the iron through barrier methods.
if the coating chips, iron is still protected through sacrificial protection
What is sacrificial protection?
when a more reactive metal can be attached to a less reactive metal so that it can oxidise and corrode first protecting the less reactive one from corrosion.
so using any metal more reactive than iron will sacrifice themselves so the iron wont corrode.