AQA · Chemistry · 8462
GCSE Chemistry: Corrosion and its prevention
Using resources · AQA GCSE Chemistry (8462), specification point 4.10.3.1. Cards are generated from the exam board's own specification for "Corrosion and its prevention", and every card links back to the page it came from. Separate science only. Specification © AQA — used with attribution.
12 flashcards · Free to study · No account needed
Study this deck
Preparing your cards…
All questions and answers
Read through the full deck, or practise recalling each answer above.
Define corrosion.
Show answer
The destruction of materials by chemical reactions with substances in the environment.
What is rusting an example of?
Show answer
Corrosion — specifically the corrosion of iron.
Which two substances are both necessary for iron to rust?
Show answer
Air (oxygen) and water.
Why does an iron nail in boiled water under a layer of oil not rust?
Show answer
Boiling removes dissolved air and the oil keeps air out, so there is no oxygen — both air and water are needed for rusting.
Why does an iron nail kept in dry air (with a drying agent) not rust?
Show answer
There is no water present — both air and water are needed for rusting.
How does painting or greasing iron prevent rusting?
Show answer
The coating acts as a barrier that keeps air and water away from the iron surface.
Name three barrier coatings that prevent corrosion.
Show answer
Greasing, painting and electroplating.
Why does aluminium not corrode further despite being reactive?
Show answer
It forms an oxide coating that acts as a barrier, protecting the metal beneath from further corrosion.
What is sacrificial protection?
Show answer
Coating or attaching a more reactive metal to iron so that the more reactive metal corrodes (is oxidised) instead of the iron.
Coating iron with zinc to protect it from rusting is called ?.
Show answer
galvanising
Why can zinc give sacrificial protection to iron?
Show answer
Zinc is more reactive than iron, so it reacts (oxidises) preferentially, sparing the iron.
Why does galvanised iron stay protected even when the zinc layer is scratched?
Show answer
Zinc is more reactive than iron, so it continues to corrode sacrificially instead of the exposed iron.
Want to create your own cards? Create a free account. AI generation uses credits.