Reactivity series Flashcards
Reactivity series
Potassium Sodium Lithium Calcium Magnesium Aluminium Zinc Iron Copper Silver Gold
Conditions under which iron rusts
Iron rusts when oxygen and water are present.
The rusting of iron may be prevented by:
barrier methods
• galvanising
• sacrificial protection
Barrier methods
Rusting may be prevented by stopping the water and oxygen getting to the iron with a barrier of grease, oil, paint or plastic.
Galvanising
(coating in zinc) also prevents water and oxygen getting to the iron, but with galvanising even if the barrier is broken the more reactive zinc corrodes before the less reactive iron. During the process, the zinc loses electrons to form zinc ions.
Sacrificial protection
Zinc blocks are attached to iron boat hulls and underground pipelines to act as sacrificial anodes. Zinc is more reactive than iron, so oxygen in the air reacts with the zinc to form a layer of zinc oxide instead of the iron.
Oil stands for…
oxydation
Rig stands for
reduction
Oxidation
Is the loss of electrons
Reduction
Is the gain of electrons
Redox
A reaction involving oxidation and reduction.
Oxidising agent
A substance that gives oxygen or removes electrons (it is itself reduced).
Reducing agent
A substance that takes oxygen or gives electrons (it is itself oxidised).
