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***2013 LC Chemistry Before/After***

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    #902
    yoppo
    Registered Users Posts: 206 ✭✭yoppo


    xJEx wrote: »
    Yoppo how did you find physics ? :))

    Ok now. I got an A2 in the mocks but my mind went fairly blank for the LC! Hopefully I'll get a B2. Not bad for doing it for a year! :pac:


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    #903
    Lonepiper
    Registered Users Posts: 22 ✭Lonepiper


    For distinguishing between ethanoic acid and ethanol I couldn't remember how we did if so I went with the iodoform test for alcohol!


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    #904
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    yoppo wrote: »
    Ok now. I got an A2 in the mocks but my mind went fairly blank for the LC! Hopefully I'll get a B2. Not bad for doing it for a year! :pac:

    Oh that's good well done! Which mock was it the one with calculating g and resistivity of nichrome? Or coplanar forces? Cause apparently one was easier


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    #905
    Copper_pipe
    Registered Users Posts: 11,553 ✭✭✭✭Copper_pipe


    I had the one with G by freefall, my teacher said it was the worst paper he's ever seen


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    #906
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    Copper_pipe wrote: »
    I had the one with G by freefall, my teacher said it was the worst paper he's ever seen

    Yeah same! She picked the hard one on purpose. I got a b3 and the rest of my class failed so i hope I go up!


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    #907
    Isco
    Registered Users Posts: 127 ✭✭Isco


    Q11 was the greatest thing I have ever seen


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    #908
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    Isco wrote: »
    Q11 was the greatest thing I have ever seen

    It was so easy and I made a balls of it hahaha


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    #909
    0mega
    Registered Users Posts: 850 ✭✭✭0mega


    I'm surprised that other people didn't like the paper. I thought it was fair and the right kind of level of challenging to distinguish between the As (not saying I definitely got one but everything on the paper was manageable).


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    #910
    wow exuberant
    Registered Users Posts: 163 ✭✭wow exuberant


    yoppo wrote: »
    For question 8 it said reagent not condition so hopefully they will take HCL and UV Light!

    were they looking for 3 seperate answers there?


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    #911
    yoppo
    Registered Users Posts: 206 ✭✭yoppo


    wow exuberant wrote: »
    We're they looking for 3 seperate answers there?

    I wrote HCL, HCL and Cl2, it was 3 marks each.


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    #912
    CookieMonster.x
    Registered Users Posts: 1,049 ✭✭✭CookieMonster.x


    yoppo wrote: »
    I wrote HCL, HCL and Cl2, it was 3 marks each.

    Is it not uv light and cl2 for the first one? HCl is a product of the reaction I think?


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    #913
    Conballz
    Registered Users Posts: 22 ✭Conballz


    TheChosenOne wrote: »
    No, the diagram was right in this regard. Water should always flow in from the bottom so it moves slowly around the tube :/

    There was no steam trap in the diagram... Although I didn't notice that and mentioned the condenser thing too :L


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    #914
    yoppo
    Registered Users Posts: 206 ✭✭yoppo


    CookieMonster.x wrote: »
    Is it not uv light and cl2 for the first one? HCl is a product of the reaction I think?

    Yep your right. When I was doing it I totally forgot it was a free radical substitution!... should have remembered that! 3 marks down.. how bad!


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    #915
    woopah92
    Registered Users Posts: 482 ✭✭woopah92


    yoppo wrote: »
    Yep your right. When I was doing it I totally forgot it was a free radical substitution!... should have remembered that! 3 marks down.. how bad!

    I got a question right that someone with a degree in chemistry didn't ;)
    F*** yeah. :cool:


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    #916
    yoppo
    Registered Users Posts: 206 ✭✭yoppo


    woopah92 wrote: »
    I got a question right that someone with a degree in chemistry didn't ;)
    F*** yeah. :cool:

    That degree is 5 years old! I need another three.

    Yoppo Mb, BCh, BAO

    :pac:


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    #917
    Say it Aint So
    Registered Users Posts: 50 ✭✭Say it Aint So


    What was the answer to the incorrect equipment setup up in Q2 for the clove oil experiment?

    I said the in and out setup for the liebig condenser?


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    #918
    Nl90
    Registered Users Posts: 19 ✭Nl90


    Say it Aint So wrote: »
    What was the answer to the incorrect equipment setup up in Q2 for the clove oil experiment?

    I said the in and out setup for the liebig condenser?

    I said that too, but I believe it's that the safety tube wasn't below the level of water !



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    #919
    Nl90
    Registered Users Posts: 19 ✭Nl90


    Lonepiper wrote: »
    For distinguishing between ethanoic acid and ethanol I couldn't remember how we did if so I went with the iodoform test for alcohol!



    I chose reacting the liquid with metal carbonate and see if the gas turn the limewater milky


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    #920
    Say it Aint So
    Registered Users Posts: 50 ✭✭Say it Aint So


    Nl90 wrote: »
    I said that too, but I believe it's that the safety tube wasn't below the level of water !


    Ah well, nothing we can do now!


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    #921
    cw67irl
    Registered Users Posts: 1,165 ✭✭✭cw67irl


    I think i put about 5 "faults" down for the clove oil,

    Tube incorrectly positioned in first section, no water in with cloves, steam tube down too low in the cloves, condenser incorrectly positioned and too much of a gap between the end of the tube and the collection flask!!

    Have to get it :-)


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    #922
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    I'm really glad I chose not to do Question 2 :) I was gonna say the liebeg thing and I was gonna do it for the easy marks for the chromatography.. But I thought for the first two bits you coud just test for unsaturated! I didn't really think I could put the same answer down for both though so I avoided it in the end. Phew! :)


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    #923
    SecondMan
    Registered Users Posts: 236 ✭✭SecondMan


    xJEx wrote: »
    I'm really glad I chose not to do Question 2 :) I was gonna say the liebeg thing and I was gonna do it for the easy marks for the chromatography.. But I thought for the first two bits you coud just test for unsaturated! I didn't really think I could put the same answer down for both though so I avoided it in the end. Phew! :)

    Q2 really wasn't as bad as everyone is saying it was. The first part consisted only of an iodoform and litmus paper test, the second part was just the addition of either bromine/potassium permanganate, part 3 was a simple description of a chromatography experiment, part 4 was easy: 120-121 degress being pure benzoic acid, and part 5 was any one mistake of a few in the diagram.


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    #924
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    Yeah but wasn't saying both the liebeg valves facing the same way was wrong? That's what I would have said
    And i havent even heard of the iodoform before! I know the benzoic acid and chromatogram was easy peasy but i would have lost marks on that question for sure!


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    #925
    SecondMan
    Registered Users Posts: 236 ✭✭SecondMan


    xJEx wrote: »
    Yeah but wasn't saying both the liebeg valves facing the same way was wrong? That's what I would have said
    And i havent even heard of the iodoform before! I know the benzoic acid and chromatogram was easy peasy but i would have lost marks on that question for sure!

    Do you do biology?


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    #926
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    SecondMan wrote: »
    Do you do biology?

    Nope i do physics, chem and applied maths.
    Why?


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    #927
    RabbitHearted
    Registered Users Posts: 101 ✭✭RabbitHearted


    i cant have been the only person who did every question on the paper, can i?


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    #928
    CookieMonster.x
    Registered Users Posts: 1,049 ✭✭✭CookieMonster.x


    RabbitHearted wrote: »
    i cant have been the only person who did every question on the paper, can i?

    I did, apart from the option part of 11.


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    #929
    [Deleted User]
    Posts: 0 ✭ [Deleted User]


    CookieMonster.x wrote: »
    I did, apart from the option part of 11.

    Same. Wasn't too fond of the option question :p


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    #930
    xJEx
    Registered Users Posts: 166 ✭✭xJEx


    Deleted User wrote: »
    Same. Wasn't too fond of the option question :p

    To all of you who did all questions more or less does that usually work for you? Like what did you get in the mock?
    I can't imagine that being the best strategy


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    #931
    CookieMonster.x
    Registered Users Posts: 1,049 ✭✭✭CookieMonster.x


    [Deleted User] wrote: »
    Same. Wasn't too fond of the option question :p

    Well attempting to learn the one we didn't do in class the morning o your exam isn't really very smart :P I think my other questions should cover me though, hopefully! I hope section A doesn't bring me down too much :/


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