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My suggested answer:
Q21) D
Q22) C
Q23) D
Q24) C
Q25) A
Q26) B
Out of the 20 chemistry question, the question I like most will be this. On the surface it looked simple, but it's testing Limiting reactant, and calculation of excess reactant.
First step is to determine the molecular formula. After you've done with your calculation, you'll get FeS.
Then next is to find out which is the the limiting reactant. After the calculation, you'll know that Fe is the limiting reactant, and of course S is in excess.
No. of mol of FeS/ No. of mol of Fe = 1/1 = 1
No. of mol of FeS = 1 x 0.125 = 0.125 mol
Mass of FeS = 0.125 x (56 + 32) = 11g
Final step is to fine out the mass of excess reactant(S).
As calculated earlier(not shown here), take the no. of mole of S minus the no. of moles of Fe. Which is 0.219 - 0.125 = 0.094 moles of S in excess
Then 0.094 x 32(Ar of S) = 3.
Answer: B
Q27) D
Q28 ) B
Q29) D
Q30) C
Q31) A
Q32) D
Q33) A
Q34) C
Q35) C
Q36) C
Q37) A
Q38 ) B
Q39) A
Q40) B
Edited for Q34, thanks kester for pointing out my mistake.
Edited by Darkness_hacker99 08 Nov `07, 2:29PM
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Assuming Darkness_hacker99 answers are correct, which I'l ltrust him on this one.
Chemistry MCQ : 18/20.
Not too bad actually.
Fermentation doesn't involve water. How silly of me =.="
Regarding Q34, Doesn't both sulphur dioxide and nitrogen oxide affect limestone ?
My ans is C.Edited by kester 08 Nov `07, 2:03PM
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Originally posted by PwnYou:may i ask
why is qns 24 C?
why is qns 40 B?
oh, i tink i got 3 wrong.
The answer is C.
The ions in ionic compound are arranged in a lattice form, that why it's called ionic lattice.
Property of Ionic compound:
1) When molten, it conducts electricity due to moving electrons.
2) have high melting points.
The answer is B.
The word 'poly' means many. Comparing the linkage which I have posted(below), there is a different between 'Amide' and 'Ester' Linkage.
If you look can see... Polyester seems to be the most similar out of the other options.
Edited by Darkness_hacker99 09 Nov `07, 8:13AM
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