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    Pt electrode is also used in cells where there are only ions used (Fe2+ to Fe3+ and e-), since there's nothing to be used as the electrode. Pt is used because it's inert and conducts electricity.
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    aaaaah, im really confused when to put moderately concentrated HCL for reagents, and when to put concentratedc H2SO4 or dilute acid etc.. help please?!
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    Esterification reactions = Concentrated Acid
    Hydroysis of esters = Dilute Acid
    Hydrolysis of amides = Moderately concentrated acid/or alkali
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    could anyone......... my hero state the conditions and reagents for all the recations/mechanisms we need to know

    also when a something in diluted in a titration like from 25cm to 250cm how to do you 'adjust' your calculations
    sorry about the lack of technical terms/poor descrisption i am not that chemistry savvy
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    (Original post by twinkabell_92)
    could anyone......... my hero state the conditions and reagents for all the recations/mechanisms we need to know
    Esterification (making an ester from a carbocylic acid and an alcohol)
    Reagent: Concentrated Sulfuric Acid
    Conditions: Heat under reflux

    Hydrolysis of an amide link/ester/phenol
    Reagent: Moderately concentrated acid (HCl or Sulfuric acid) or alkali (NaOH)
    Conditions: Heat under reflux

    Oxidation of Alcohols
    Primary alcohol ---> aldehyde
    Reagent: Acidified Potassium Dichromate (acidified with concentrated sulfuric acid)
    Conditions: Distill

    aldehyde ---> carboxylic acid
    Reagent: Acidified Potassium Dichromate (acidified with concentrated sulfuric acid)
    Conditions: Heat under reflux

    secondary alcohol ---> ketone
    Reagent: Acidified Potassium Dichromate (acidified with concentrated sulfuric acid)
    Conditions: Heat under reflux


    And I believe that's all we need to know. Correct me if I'm wrong.
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    (Original post by parallal)
    Esterification (making an ester from a carbocylic acid and an alcohol)
    Reagent: Concentrated Sulfuric Acid
    Conditions: Heat under reflux

    Hydrolysis of an amide link/ester/phenol
    Reagent: Moderately concentrated acid (HCl or Sulfuric acid) or alkali (NaOH)
    Conditions: Heat under reflux

    Oxidation of Alcohols
    Reagent: Acidified Potassium Dichromate (acidified with concentrated sulfuric acid)
    Conditions: Heat under reflux

    And I believe that's all we need to know. Correct me if I'm wrong.
    Just to quickly add... for Oxidation of alcohols, when you are going from a primary alcohol to an aldehyde, you Distill, you don't heat under reflux.
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    mug what are you on about yes you do.
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    (Original post by AGM)
    Just to quickly add... for Oxidation of alcohols, when you are going from a primary alcohol to an aldehyde, you Distill, you don't heat under reflux.
    Just checked my notes. You are right. I'll go fix that now.
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    (Original post by smj14)
    aaaaah, im really confused when to put moderately concentrated HCL for reagents, and when to put concentratedc H2SO4 or dilute acid etc.. help please?!
    Conc H2SO4 OR HCl to make esters from Carboxylic Acid + Alcohol
    No catalyst for making esters from Phenol + Acyl Chloride, it goes at room temp.

    Hydrolysing Esters (Adding a molecule back in)
    Dilute H2SO4 OR preferred is an Alkali catalyst because it goes to completion (such as NaOH)

    Hydrolysing Amides (to a carboxylate ion and an amine) is Moderately Concentrated Acid

    Think that's all the ones that are needed
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    Does anyone else think that June 2010 paper was extremely hard?

    I mean I was getting 75-80 in all the past papers till that one where I got like 69...it was so difficult!
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    (Original post by parallal)
    Hydrolysis of an amide link/ester/phenol
    Reagent: Moderately concentrated acid (HCl or Sulfuric acid) or alkali (NaOH)
    Conditions: Heat under reflux

    It's definately only Dilute Sulfuric they'll accept here, been caught out by that in a few past papers. Worth noting that with an alkili catalyst the reaction goes to completion too
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    (Original post by Darthdevidem)
    Does anyone else think that June 2010 paper was extremely hard?

    I mean I was getting 75-80 in all the past papers till that one where I got like 69...it was so difficult!
    Yeah! That electrode potential question was horrible :|
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    Any essential storylines we should have a quick read over of guys? Just read over the ethics around DNA databases, which was a past paper question
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    (Original post by joestevens2092)
    Any essential storylines we should have a quick read over of guys? Just read over the ethics around DNA databases, which was a past paper question
    I reckon BOS process cause i havent seen that in like the actual papers for this spec yet
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    (Original post by doomhalo)
    Yeah! That electrode potential question was horrible :|
    lol thats the one I'm doing well on. I completely flopped on Q1 and 2 though, lost 15 marks in them both combined
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    (Original post by Darthdevidem)
    Does anyone else think that June 2010 paper was extremely hard?

    I mean I was getting 75-80 in all the past papers till that one where I got like 69...it was so difficult!
    June i got 77/90 or was it 74? I got in the 70s
    69 is A* isnt it?
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    (Original post by Darthdevidem)
    lol thats the one I'm doing well on. I completely flopped on Q1 and 2 though, lost 15 marks in them both combined
    Yeah was pretty tricky throughout, although I imagine the boundary was a fair bit lower.
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    (Original post by Mr-Joey-C)
    I reckon BOS process cause i havent seen that in like the actual papers for this spec yet
    But apprantly BOS isn't listed on the spec...
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    what is bos?
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    (Original post by smj14)
    what is bos?
    Basic Oxygen Steeling Making Process.

    All you need to know is... steel is at first full of impurities, they get rid of the sulphur with a blast of Magnesium. And get rid of other impurities like Carbon(which makes steel brittle) with a blast of oxygen. Different levels of other elements in the steel give it different properties.

    Recycled steel is added to act as a coolant and a source of recycled steel.
 
 
 
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