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temperature and corrosion at great depths (1 Viewer)

tamia

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can anyone explain dotpoint 9.6.5 when it says 'predict the effect of low temperatures at great depths on the rate of corrosion of a metal'. I can't seem to find any info in txt bks.


thanks alot!
 

xiao1985

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as depth increases:

temperature decreases,
o2 concentration decreases...

and since o2 is the necessary factor for the normal corrosion to occur, and high temperature speed the corrsion process, the lack of o2 and low temp predict minimal corrosion should occur, if any...

it leads nicely to the desulfurvibrio bacteria, which reduces sulphate ions and at the same time oxides Fe to cause an unexpected corrosion...
 

gershy

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The O2 concentration actually increases with a drop in temperature. However little O2 is available due to (a) lack of contact with the atmosphere (b) lack of photosynthesis and (c) consumption by respiration. The temperature and O2 stories should be treated separately.
 

BlackJack

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You should note that it's the solubility of gases(O2) that increases with drops in temperature. But all the dissolved O2 that goes into the ocean can't reach the bottom.
 

Atotoi

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*Yawn*...Corrosion sucks.. what textbooks do you have?
Im using an old "Conquering Chemistry" book, "Chemistry Contexts 2" and "Surfing Chemistry - Shipwrecks etc" .
 

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