topic 10 - using resources (3. corrosion)

Question 1

what is corrosion

Answer 1

when a metal is gradually destroyed by reacting with substances in the environment

Question 2

example of corrosion and equation

Answer 2

iron rusting

iron + oxygen + water -> hydrated iron oxide

Question 3

when does corrosion happen

Answer 3

when a surface of a material is exposed to air

Question 4

what else corrodes when exposed to air

Answer 4

aluminium

Question 5

how to prevent corrosion

Answer 5

creating a barrier
sacrificial methods
both

Question 6

ways to create a barrier to prevent corrosion

Answer 6

painting a metal
electroplating using electrolysis to reduce metal ions onto an iron electrode
oiling or greasing used when moving parts are involved

Question 7

what is the sacrificial method to preventing corrosion

Answer 7

placing a more reactive metal with the metal you want to protect
water and oxygen react with the sacrificical method instead of the less reactive metal