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General Thoughts: Chemistry (1 Viewer)

Madridismo

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Yes, you can. But it's not the most accurate method due to the many other external factors that can influence the amount of organic matter in the system and amount of DO. Then again, you'll probably get the marks anyway.
I mentioned how the algal bloom uses up the DO for other organisms that won't be able to survive, but I mentioned that it can also be monitored through cation testing, since nitrates and phosphates that are able to be tested. Would that be alright?
 

someth1ng

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I mentioned how the algal bloom uses up the DO for other organisms that won't be able to survive, but I mentioned that it can also be monitored through cation testing, since nitrates and phosphates that are able to be tested. Would that be alright?
Those are anions.
 

sarah jones

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Hi!

What was the answer for "why was ethanol added"????? -- for the aspirin question
 

traiwit

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I just searched around. It is because aspirin is only slightly soluble in water and hence, a more non-polar solvent is needed (ethanol) to fully dissolve it.
Oh its only 1 mark, hopefully my answer is okay >..<
 
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For the aspirin tablet question, weren't we meant to discard the first titration as a rough estimation??
 

traiwit

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For the aspirin tablet question, weren't we meant to discard the first titration as a rough estimation??
Yes i did, average only 2nd and 3rd and got like 16.525 maybe ? I dont remember ==*
 
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Yes i did, average only 2nd and 3rd and got like 16.525 maybe ? I dont remember ==*
Ok thanks..one more question (to anyone).. for the electrochemical cell question where u had to talk about the collaboration of scientists, was it ok to use the mercury cell as an electrochemical cell, cos I noticed most ppl were using lead-acid cell :/
 

LifeBoats

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I mentioned how the algal bloom uses up the DO for other organisms that won't be able to survive, but I mentioned that it can also be monitored through cation testing, since nitrates and phosphates that are able to be tested. Would that be alright?
Yeah as Someth1ng mentioned, those are anions. So there is no other feasible way of determining their concentration other than Colourimetry (Or Gravimetric Analysis but lol). Algal blooms do use up DO but they are not the sole reason that levels in DO decrease; large amounts of waste in water, increase in temp etc. So, it's alright but I don't think you'll get full marks.
 

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