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Need HELP on CIE Chemistry AS/A2 level

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The SMA:

--- Quote from: nid404 on May 04, 2010, 05:08:53 am ---14) C SO2 always first convert to SO3...so basically even when you do reaction with water, it converts to sulphurous acid first, sulphuric later

17) D because if you notice the reaction with iodide. I2 as vapour is formed with H2SO4...ox state 0  whereas with H3PO4, it is HI that forms..ox state of I is -1 So higher ox state with sulphuric acid, which shows it oxidises better...

Q22) A & B ruled out at the very start....no chiral possible, no isomerism either
        C not possible cause you can't have a chiral...try substituting an  H with a chlorine...try all possible subs ....no chiral..Hence D (second from left substituted, you get chiral)

I have to leave urgently....I'll get back from school and answer :)

--- End quote ---

allright Nid, i'll wait for the other explanations later  :)

By the way, I understood q14 & 17 now.
but i'm a lil bit confused on q22), do you mean substitute the CH3- group on the left with Cl
so ClCH=CHCH2CH3
but this is the confusing part..i can't identify which one is the Chiral carbon atom..
please correct me if i'm wrong

nid404:
naah..... I meant
CH2=CHC*H(Cl)CH3  (*=chiral centre)

nid404:
Q31)Can't really think how to explain 31...let me look up for something

Q35) It can't be 1 because halogen-halogen bond energy is related to atomization.. .They always exists as diatomic molecules. when you've eliminated the 1st option, obv ans is 2&3(C)
The weaker the van der waals forces, more volatile it is.

Q38) has to be D. 2 and 3 are much obviously flammable.

The SMA:

--- Quote from: nid404 on May 04, 2010, 09:51:16 am ---naah..... I meant
CH2=CHC*H(Cl)CH3  (*=chiral centre)

--- End quote ---

got it now. Thanks! ^^

The SMA:
ok, take your time..
I tends to score low in section B  :-[ i don't find it easy to ans questions from section B. :S

oh yeah and for Q8 of the same year, why is B is not the answer?
the ans is actually D though..

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