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Effect of Temperature on Corrosion

I am doing a science project on how temperature has an effect on the rate of corrosion. I conducted my experiments and found out that metals start to show signs of corrosion at higher temperatures than those at lower temperatures. I researched how corrosion works and I think I have a pretty good understanding of how it works. I am not sure however about how temperature may have an effect. I think it have something to do with the transfer of electrons between the anode and cathode. I believe the temperature excites the electrons and speeds up the reaction. This is just my guess and I have no real basis. I was hoping you could tell me the real answer that temperature has an effect on corrosion.

Mitchell F.
Student - Bowie, Maryland
2007

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2007

Mitchell

Congratulations. You have just hit on a branch of science known as thermochemistry - the effect of heat on reactions. This is a branch of thermodynamics. Books on the subject are thick and loaded with mathematics so you probably won't want to dig too deep at this stage.
Three simple points.
For 'excites the electrons' think 'adds energy to the system'. Reactions need some energy to get them going and the more the faster.
At Absolute Zero -273 deg C Molecules have no heat energy.
As a simple 'rule of thumb' for many reactions 10 °C will double the rate of reaction.

Geoff Smith
Hampshire, England