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    (Original post by Kaya22)
    nope
    Thank you!
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    (Original post by vaishnagaraj)
    Do we need to memorise the pH indicators and their Ph ranges?
    The only one we need to memorise is phenolphthalein which is 8.3-10 and colourless at low pH and pink/red at high pH (they allow pink or red in all mark schemes from past papers.
    Good Luck
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    How would you name a compound which shows e/z isomerism, having 2 methyl groups on one side and one bromine group on the other side with one h atom? Do you have to consider priority or something?
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    (Original post by Hadigy)
    How would you name a compound which shows e/z isomerism, having 2 methyl groups on one side and one bromine group on the side with one h atom? Do you have to consider priority or something?
    Alphabetical order so bromo comes first
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    (Original post by thehollowcrown)
    Alphabetical order so bromo comes first
    Thanks. So would it be Z or E isomerism?
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    (Original post by Hadigy)
    Thanks. So would it be Z or E isomerism?
    actually the compound you have described doesn't have the same functional group attached to either carbon so it can't be E/Z isomerism
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    (Original post by Anon_98)
    Hey guys, just wanted to say that if anyone wanted a quick summary on everything you need to know for the course as a bit of last minute revision stuff then I made a thread. Don't know if it'll be useful but here:

    http://www.thestudentroom.co.uk/show....php?t=4159211

    Anyway good luck, hope it goes well for you all. :woo:
    You are so great!
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    (Original post by Hadigy)
    How would you name a compound which shows e/z isomerism, having 2 methyl groups on one side and one bromine group on the other side with one h atom? Do you have to consider priority or something?
    Z-1-bromo-2-methyl-prona-1-ene.
    Z as highest priorities are on the same side of the double bond.
    1 bromo as it is on the first carbon in chain.
    2 methyl as it is on 2nd carbon in chain.
    1-ene as double bond is between 1st and 2nd carbons.
    And then just alphabetical order for naming additional groups.
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    (Original post by thehollowcrown)
    actually the compound you have described doesn't have the same functional group attached to either carbon so it can't be E/Z isomerism
    why wouldn't it be z/e isomerism?
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    Hey Guys for an acidic buffer if you ADDED OH+ what answer would you put???

    1) They react with H+ to produce water and shift eqm to the right
    OR
    2) They react with HX to produce X- and water
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    (Original post by thehollowcrown)
    actually the compound you have described doesn't have the same functional group attached to either carbon so it can't be E/Z isomerism
    http://www.chemguide.co.uk/basicorg/isomerism/ez.html reading through the first couple of paras on this page suggests it would have z/e isomerism. I'm pretty sure it's any four groups which you then have to determine which are higher priority?
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    (Original post by bethl303)
    You are so great!
    I'm glad you found it helpful! GL
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    (Original post by nutcase13)
    m+4 peak?
    How would you convert sodium salts back to fatty acids?
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    (Original post by shiney101)
    How would you convert sodium salts back to fatty acids?
    I think just add acid such as HCl and the Na+ would be substituted for the H+ to reform the carboxylic acid
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    (Original post by Ebaysass)
    Hey Guys for an acidic buffer if you ADDED OH+ what answer would you put???

    1) They react with H+ to produce water and shift eqm to the right
    OR
    2) They react with HX to produce X- and water
    would the oh not be oh- , and i don't think that would be a question usually you'd have to work out the moles of it and subtract it from the ion and add it to the acid to work out a new pH or something
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    (Original post by Jackpalmer1996)
    would the oh not be oh- , and i don't think that would be a question usually you'd have to work out the moles of it and subtract it from the ion and add it to the acid to work out a new pH or something
    yeh sorry meant oh-, oh ok i had just had a look at it came up in 2011 paper i think! They accepted both answers to be fair
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    Guys does anyone know how nuc add-elim mechanisms work with acid anhydrides?
    Why you attack the c=o. Do you just attack one or both of them?
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    (Original post by Ebaysass)
    yeh sorry meant oh-, oh ok i had just had a look at it came up in 2011 paper i think! They accepted both answers to be fair
    Think i've just come across it actually, the question where it says if oh- is added to a buffer how does the pH remain constant? If so then yeah my bad, i would just say how the oh- reacts with h+ which cancels out the effect of the base being added and eqm. shifts to rebalance concs.
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    (Original post by Jackpalmer1996)
    Think i've just come across it actually, the question where it says if oh- is added to a buffer how does the pH remain constant? If so then yeah my bad, i would just say how the oh- reacts with h+ which cancels out the effect of the base being added and eqm. shifts to rebalance concs.
    its simply OH- reacts with H+ equilibrium will move to the right hand side so the the h+/a- remains almost the same, from what i remember.
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    (Original post by Super199)
    Guys does anyone know how nuc add-elim mechanisms work with acid anhydrides?
    Why you attack the c=o. Do you just attack one or both of them?
    Say you are reacting it with an alcohol, the H fro the alcohol would add to one part of the anhydride to create a carboxylic acid, then the other part would react with
    the remainder to create an ester.

    I don't know if this made much sense...
 
 
 
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