1. Calderglen High School
corrosion 1 2 3 4 5 6 7 8 9 10 11 12 13 14
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2. Calderglen High School1
What is corrosion?
answer
A chemical reaction involving a metal changing from an element to a compound
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3. Calderglen High School2
Magnesium provides iron with sacrificial protection. In which direction do electrons flow?
answer
From magnesium to iron
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4. Which metal is used to galvanise iron?3
Which metal is used to galvanise iron?
answer
zinc
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5. Calderglen High School4
Which metal RUSTS?
answer
iron
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6. Give an example of how iron can be physically protected.5
Give an example of how iron can be physically protected.
answer
Paint, grease, tin-plate, electroplate, galvanising, coat with plastic
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7. How does a physical barrier protect iron against rusting?6
How does a physical barrier protect iron against rusting?
answer
Barrier to water and air (oxygen)
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8. Name the two main ways of protecting iron from rusting.7
Name the two main ways of protecting iron from rusting.
answer
Physical protection
and
sacrificial protection
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9. Calderglen High School8
Should a metal be ABOVE or BELOW iron in the electrochemical series to provide sacrificial protection
answer
ABOVE
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10. Calderglen High School9
Chromium plated steel rusts quickly when scratched. Compared to iron is chromium more reactive or less reactive.
answer
Less reactive
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11. Why does salt speed up corrosion?10
Why does salt speed up corrosion?
answer
Salt is an electrolyte
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12. How do salt and acid rain affect corrosion?11
How do salt and acid rain affect corrosion?
answer
Speeds it up
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13. Calderglen High School12
What is the test to show that rusting has occurred (test for Fe2+ ions?)
answer
Ferroxyl indicator
turns blue
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14. What two conditions are required for rusting to take place?13
What two conditions are required for rusting to take place?
answer
Water and oxygen
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15. What type of reaction takes place when a metal corrodes?14
What type of reaction takes place when a metal corrodes?
answer
oxidation
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