Killed by multiple choice? (1 Viewer)
- Thread starter 4theHSC
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yeh i agree with pH --> floc --> settling --> pH (later)
i put pH adjustment AFTER floc & settling
but i didn't realise that chlorination was there in step 5. i think that was the real keyword in the question that meant you had to put pH before floc & settling.
let's hope they accept both answers!
i put pH adjustment AFTER floc & settling
but i didn't realise that chlorination was there in step 5. i think that was the real keyword in the question that meant you had to put pH before floc & settling.
let's hope they accept both answers!
mR sinister
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- 2009
Yep this was a really screwed up multiple choice...
And what did every1 get for question 14,
i done the calculation and got A, but thats not what most ppl got....
Also Question 8 would be B would it not?
CO3^2- makes a percipitate with pb^2+
But most ppl got A.. hmm
And what did every1 get for question 14,
i done the calculation and got A, but thats not what most ppl got....
Also Question 8 would be B would it not?
CO3^2- makes a percipitate with pb^2+
But most ppl got A.. hmm
it is A, because it has iodine, sure it could be B, except it said "UNAMBIGUOUSLY identify" and carbonate ions also precipitates with calcium (i.e limestone) and sodium (i.e sodium carbonate as seen in the solvay process).
in relation to the pH question, by added lime to the water, this chemical additive is part of the flocculation step, hence it is not a step by it self. Thus D is the right answer as pH adjustment is a completely different process which occurs after chlorination.
I did the EXACT same thing. lol silly us
carlytse621
Member
I just found a conquering chem exercise sheet and it has a diagram of water treatment
It said pH adjustment is at the end
It said pH adjustment is at the end