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shipwrecks, corrosion n conservation (1 Viewer)

console

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did everyone put oxygen as a factor influencing the rate of corrosion?...or anaerobic bacteria?
 

console

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ummm they said deep sea wrecks....that means the concentation of oxygen....but it said rate of corrosion...then agian it could be bacteria.... prob either answer is fine
 

stef.

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i think both wouldve been fine..
if u put oxygen (lack of it) then the rate of corrosion would decrease
if u put anaerobic bacteria, then the rate of corrosion would increase

??
 

stef.

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MuffinMan said:
the acidity of the electrolyte (aka seawater) :D
more acidic more corrosion
the sea isnt acidic is it??
i thought the acidic nature of deep sea would be from the anaerobic bacteria reducing sulfate and producing H+ in the reduction.

SO4 + 5h20 + 8e ==> HS- + 9OH-

im glad confusion comes in after the exam..
 

Dumsum

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The 7 mark question was straight out of a past English paper, I swear...
 

rama_v

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I wrote sulfate reducing bacteria
I think i went overboard when I wrote the full name of the bacteria with equations :p
 

stef.

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Dumsum said:
The 7 mark question was straight out of a past English paper, I swear...

as sad as this may sound..i had fun with that question..well the most fun u can have when doing chem...cos you just re'tell them alllll you know about corrosion prevention/protection..and thats a very big part of my shipwrecks understadning..
 

MuffinMan

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stephanie_168 said:
the sea isnt acidic is it??
i thought the acidic nature of deep sea would be from the anaerobic bacteria reducing sulfate and producing H+ in the reduction.

SO4 + 5h20 + 8e ==> HS- + 9OH-

im glad confusion comes in after the exam..
acidic due to the presence of sulfate producing bacteria...
 

Dumsum

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stephanie_168 said:
as sad as this may sound..i had fun with that question..well the most fun u can have when doing chem...cos you just re'tell them alllll you know about corrosion prevention/protection..and thats a very big part of my shipwrecks understadning..
Yeah I ended up spitting out 3 pages, lol. I did the elective after the multiple choice, so it was still early on which was good :)
 

Tulipa

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stephanie_168 said:
as sad as this may sound..i had fun with that question..well the most fun u can have when doing chem...cos you just re'tell them alllll you know about corrosion prevention/protection..and thats a very big part of my shipwrecks understadning..
me too!

i loved it, it was like YES 7 marks right there cause i had just reviewed in depth that last night.

i actually loved shipwrecks overall.

and i put anaerobic bacteria. hopefully thats right
 

MuffinMan

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Tulipa said:
me too!

i loved it, it was like YES 7 marks right there cause i had just reviewed in depth that last night.

i actually loved shipwrecks overall.

and i put anaerobic bacteria. hopefully thats right
hahhahahah ditto to that :D
i thought the option was easier than the core lol
thanks to indepth revision of shipwrecks last night
hmms...now what do i do with my success one chemistry book?
lol
 

Captain Gh3y

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That 7 mark question was SO english-ish. I don't see why they even bothered with the statement at all, why not just ask us directly about methods of preventing corrosion? There's enough to talk about for it to be a 7 mark question without the need for "discuss this statement, with reference to your prescribed texts and two other texts of your own choosing" being added.

Seriously, it doesn't make the question any more effective in testing our understanding of chemistry, or address anything more in the syllabus. It just confuses people with words for no reason. Why bother?

Of my 500 posts, at least 400 are bagging english or english-in-science...
 

MuffinMan

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yeah i thought they meant the conservation of artefacts and i had to cross it out and start again *vent* lol
 

rama_v

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Captain Gh3y said:
That 7 mark question was SO english-ish. I don't see why they even bothered with the statement at all, why not just ask us directly about methods of preventing corrosion? There's enough to talk about for it to be a 7 mark question without the need for "discuss this statement, with reference to your prescribed texts and two other texts of your own choosing" being added.

Seriously, it doesn't make the question any more effective in testing our understanding of chemistry, or address anything more in the syllabus. It just confuses people with words for no reason. Why bother?

Of my 500 posts, at least 400 are bagging english or english-in-science...
You could have included BNW BR if given the chance. Just state stuff like "advances in chemistry are detrimental to society, because even though corrosion resistant paints can be made, these ultimately destroy our love of the wild and natural processes such as rusting, as is elucidated through the metropolis of LA in 2019, which is clearly a victim of a nuclear holocaust"

:D
 

MuffinMan

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rama_v said:
You could have included BNW BR if given the chance. Just state stuff like "advances in chemistry are detrimental to society, because even though corrosion resistant paints can be made, these ultimately destroy our love of the wild and natural processes such as rusting, as is elucidated through the metropolis of LA in 2019, which is clearly a victim of a nuclear holocaust"

:D
damn, the option makes the core topics look HARD
(not that they were hard, just option i studied in depth) :D
 

AreYouAlright?

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Q b) ii.

What did you guys put that happened. I put that it was like a metal displacement reaction as the Magnesium is more active than the iron(II) solution Iron would precipitate out of solution onto the bottom of the beaker and that nothing would happen with the Iron nail because magnesium solution is more active than it.

OR did you say that it worked like a galvanic cell? With Iron being reduced at the nail... i'm going to be so pissed off if i got that wrong. :(
 

avalonian

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hey guys ive been talkin to some teachers that were bitching to me, like in physics, music etc and this is the general gist ive gotten from them, explaining the 7 mark question:

(call me sexist but this is pretty factual)

Studies have proven that girls answer essay questions better than scientific short answers and that stuff, whilst guys are better at short answers and not so good at the essay stuff. It may not be so for you, but in general its true.
The board of studies about 7 years ago noticed that there werent enough girls doing some subjects, most obviously the sciences, chemistry, physics etc so to encourage more girls to do the course they've made it more of an essay based course, however in doing so (most obvious in physics) they've lost the gist of the subject, and then arent really teaching 'real' (university) physics, hence why ppl r often shocked when they decide to do a science at uni, its much more in depth and factual than the course.
So the essays are to attract girls to the course, hence the essay-ish 7 marker, obviously chemistry is taking the same turn as physics.
 

gogogadgetbrain

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AreYouAlright? said:
What did you guys put that happened. I put that it was like a metal displacement reaction as the Magnesium is more active than the iron(II) solution Iron would precipitate out of solution onto the bottom of the beaker and that nothing would happen with the Iron nail because magnesium solution is more active than it.

OR did you say that it worked like a galvanic cell? With Iron being reduced at the nail... i'm going to be so pissed off if i got that wrong. :(
yeah i said the nail also rusted because it wasnt connected to the magnesium and therefore wasnt cathodically protected...also when iron ions are displaced by the magnesium, the magnesium ribbon would dissapear into solution or untill all the iron ions had been removed .

but also the iron forming on the magnesium may eventually rust also..?
 

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