Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

**Chemistry...Before/After

Options
1…78101213…27

Comments

  • Options
    #272
    DepoProvera
    Registered Users Posts: 404 ✭✭DepoProvera


    Mista wrote: »
    Hydrated. My bad :P the water of crystallisation one :)

    You scared me there.. Yeah I hope that comes up :)


  • Options
    #273
    Liveforrugby
    Registered Users Posts: 343 ✭✭Liveforrugby


    Mista wrote: »
    No bother :) Your given them, or the ratios.. all you need are the ratios :P

    My teachers convinced that hydrates sodium carbonate is coming up :P And I think that volatile liquid has a good chance of appearing... hate that one :( As for organic, maybe ethanal/ethanoic acid.. but I'm going over eveything, not gna do a Plath on chemistry :P

    Ahh c'mon. Where's the fun when you have everything learnt off? Where's the risk? You might as well say no to life then if you're going to be like that


  • Options
    #274
    Saracarroll
    Registered Users Posts: 64 ✭✭Saracarroll


    Liveforrugby wrote: »
    Why is sulfuric acid needed in the preparation of ethanal. What's it's function?

    To supply H+'s

    3(c2h5oh) + (cr2o7)2- + 8h+ = 3(ch3cho) + 2(cr3+) + 7(h20)


  • Options
    #275
    Mista
    Registered Users Posts: 183 ✭✭Mista


    Hayezer wrote: »
    Thanks a mill :D!

    No bother :)
    DepoProvera wrote: »
    You scared me there.. Yeah I hope that comes up :)

    Me to :) I've finally learned how to find x! :D
    Liveforrugby wrote: »
    Ahh c'mon. Where's the fun when you have everything learnt off? Where's the risk? You might as well say no to life then if you're going to be like that

    Haha, ah I fecked up one subject, not gna do that on another :P Besides, I love chemistry :)


  • Options
    #276
    Hayezer
    Registered Users Posts: 652 ✭✭✭Hayezer


    Let's say with an ester like methyl ethanoate, is methanol the alcohol and ethanoic acid the carb. acid? Or is it the other way around :confused:?


  • Advertisement
  • Options
    #277
    DepoProvera
    Registered Users Posts: 404 ✭✭DepoProvera


    Hayezer wrote: »
    Let's say with an ester like methyl ethanoate, is methanol the alcohol and ethanoic acid the carb. acid? Or is it the other way around :confused:?

    Yep that's right. It helps if you draw it out you can see the carboxylic acid in the structure.


  • Options
    #278
    paddyhes
    Registered Users Posts: 81 ✭✭paddyhes


    Hayezer wrote: »
    Let's say with an ester like methyl ethanoate, is methanol the alcohol and ethanoic acid the carb. acid? Or is it the other way around :confused:?

    Yep that's it.
    Alcohol makes up the first part.
    Carb. acid makes up the second.


  • Options
    #279
    TheHazer
    Registered Users Posts: 9 ✭TheHazer


    Naomi00 wrote: »
    I can see why they'd want a better version of experiments if their book is as bad as ours, 'Chemistry Live' :\

    That's written by the same man who makes out the chemistry test every year :rolleyes:


  • Options
    #280
    ivanh
    Closed Accounts Posts: 72 ✭✭ivanh


    We don't need to know the equations for soap, ethanal or ethanoic acid


  • Options
    #281
    ivanh
    Closed Accounts Posts: 72 ✭✭ivanh


    Liveforrugby wrote: »
    Why is sulfuric acid needed in the preparation of ethanal. What's it's function?
    Provides H+ ions for the reaction!


  • Advertisement
  • Options
    #282
    DepoProvera
    Registered Users Posts: 404 ✭✭DepoProvera


    ivanh wrote: »
    We don't need to know the equations for soap, ethanal or ethanoic acid

    We do need to know soap equation.. They asked half of it before.


  • Options
    #283
    Mista
    Registered Users Posts: 183 ✭✭Mista


    ivanh wrote: »
    We don't need to know the equations for soap, ethanal or ethanoic acid

    We definitely do for soap.


  • Options
    #284
    ivanh
    Closed Accounts Posts: 72 ✭✭ivanh


    Anyone not know the scientists and what they discovered in Chapter 1?

    I just can't get them into my head, but I've an awful feeling they'll be a big chunk of Q5 or at least a part of Q4.. :/

    Can anyone summarise them for me? It would be greatly appreciated :D


  • Options
    #285
    reznov
    Registered Users Posts: 921 ✭✭✭reznov


    Know all equations if you want an A1.
    Don't expect an A1 if you haven't every page memorised.


  • Options
    #286
    ivanh
    Closed Accounts Posts: 72 ✭✭ivanh


    Mista wrote: »
    We definitely do for soap.
    Oh yeah sorry my bad, but the other two, definitely not :)


  • Options
    #287
    DepoProvera
    Registered Users Posts: 404 ✭✭DepoProvera


    ivanh wrote: »
    Anyone not know the scientists and what they discovered in Chapter 1?

    I just can't get them into my head, but I've an awful feeling they'll be a big chunk of Q5 or at least a part of Q4.. :/

    Can anyone summarise them for me? It would be greatly appreciated :D

    I doubt they'll come in in Q5! Came up last two years. I'd say its trends and bonding(first ionisations is my bet). Definitely for Q4 though :P


  • Options
    #288
    Mista
    Registered Users Posts: 183 ✭✭Mista


    ivanh wrote: »
    Oh yeah sorry my bad, but the other two, definitely not :)

    No bother :) And yea, only realised that now you've mentioned it.. thank god for small mercies anyway! :D


  • Options
    #289
    Spattersonox
    Registered Users Posts: 134 ✭✭Spattersonox


    I need a B2... FCUK


  • Options
    #290
    reznov
    Registered Users Posts: 921 ✭✭✭reznov


    ivanh wrote: »
    Oh yeah sorry my bad, but the other two, definitely not :)

    If you want a B1, don't memorise the other two.


  • Options
    #291
    DepoProvera
    Registered Users Posts: 404 ✭✭DepoProvera


    reznov wrote: »
    If you want a B1, don't memorise the other two.

    Bold Reznov!


  • Advertisement
  • Options
    #292
    reznov
    Registered Users Posts: 921 ✭✭✭reznov


    DepoProvera wrote: »
    Bold Reznov!

    Only the top students achieve an A1.
    The top students practically have university level knowledge coming into the exam.
    Best way to see if you're capable is to sit a university chemistry exam (3rd year recommended). If you achieve a high grade, you're ready for the leaving.


  • Options
    #293
    ivanh
    Closed Accounts Posts: 72 ✭✭ivanh


    reznov wrote: »
    If you want a B1, don't memorise the other two.
    What are you on about?


  • Options
    #294
    earwax_man
    Registered Users Posts: 264 ✭✭earwax_man


    I just have to look over definitions and experiments again, and I'm all set. These are all of them that have been asked since 2002. :)

    Page one
    Page two


  • Options
    #295
    Spattersonox
    Registered Users Posts: 134 ✭✭Spattersonox


    earwax_man wrote: »
    I just have to look over definitions and experiments again, and I'm all set. These are all of them that have been asked since 2002. :)

    Page one
    Page two

    Legend!


  • Options
    #296
    DepoProvera
    Registered Users Posts: 404 ✭✭DepoProvera


    earwax_man wrote: »
    I just have to look over definitions and experiments again, and I'm all set. These are all of them that have been asked since 2002. :)

    Page one
    Page two

    Hmm you have nice writing <3


  • Options
    #297
    Coeurdepirate
    Registered Users Posts: 2,576 ✭✭✭Coeurdepirate


    Lads, all I know is equilibrium and fuels & heats :( if i manage to get the rest of organic, water, oxidation/reduction, some atomic theory and the organic experiments and titrations done by tomorrow, should I pass honours? Like I'd be happy with a D3.


  • Options
    #298
    ei.sderob
    Closed Accounts Posts: 108 ✭✭ei.sderob


    reznov wrote: »
    Only the top students achieve an A1.
    The top students practically have university level knowledge coming into the exam.
    Best way to see if you're capable is to sit a university chemistry exam (3rd year recommended). If you achieve a high grade, you're ready for the leaving.

    Are you alright? Mentally that is.


  • Options
    #299
    ashalingable
    Registered Users Posts: 21 ✭ashalingable


    ei.sderob wrote: »
    Are you alright? Mentally that is.

    Seconded!


  • Options
    #300
    ei.sderob
    Closed Accounts Posts: 108 ✭✭ei.sderob


    Anyone have the definition for a covalent bond and a sublevel? Grand for the rest on those links.


  • Advertisement
  • Options
    #301
    HeaneyBabe
    Registered Users Posts: 288 ✭✭HeaneyBabe


    Coeurdepirate wrote: »
    Lads, all I know is equilibrium and fuels & heats :( if i manage to get the rest of organic, water, oxidation/reduction, some atomic theory and the organic experiments and titrations done by tomorrow, should I pass honours? Like I'd be happy with a D3.

    Yeah just make sure you know all your organic experiments because they could ask anything on organic


Advertisement