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    (Original post by Jamesrb)
    Well...the papers before 2009 were much easier lol
    lol thats exactly why i asked.. i wanted reassurance that the 2010 paper was hard by luck, not by the new specification..

    ahh im gonna fail tomorrow.. i wish i sat this before the new spec came out
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    (Original post by bla_bla_bla_blaa)
    wow why was my other acc perm banned?

    anyway.. is the new spec any different to the old one? silly question i know but i can't spot the difference lol..

    and to clear a few things up:
    alkene to alcohol: heat under reflux with concentrated sulphuric acid (or heat with steam under high pressures?)
    alcohol to alkene: ??
    alcohol to aldehyde/ketone: oxidise primary and/or secondary alcohols

    alcohol - alkene = Al(2)0(3), 300 degrees, 1 atm.
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    (Original post by najeezy)
    alcohol - alkene = Al(2)0(3), 300 degrees, 1 atm.
    where Al2O3 is the catalyst, and 300 degrees 1 atm is temp and pressure right?
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    if you get a question where you're given the concentration (in moldm^3) and volume in cm^3, do you multiply them then divide by 1000 to get moles?

    or do you divide by 1000 when you are given volume in dm^3?
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    (Original post by najeezy)
    alcohol - alkene = Al(2)0(3), 300 degrees, 1 atm.
    lastly alkene to alcohol = alkene + H(2)0, conditions/reagents = H(3)PO(4), 300 degrees also 60 atm.
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    (Original post by bla_bla_bla_blaa)
    where Al2O3 is the catalyst, and 300 degrees 1 atm is temp and pressure right?
    mhmm.
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    do you always convert grams to kg ?
    and so c-f shortest bond = strongest. longer bonds down group, bond enthalpy of c-hals decreases down group with larger atom?
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    (Original post by rainbowsss)
    do you always convert grams to kg ?
    and so c-f shortest bond = strongest. longer bonds down group, bond enthalpy of c-hals decreases down group with larger atom?
    You convert KG to grams.
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    electronegativity is the ability to attract bonding electrons from an atom

    true or false? correct answer wins a rep worth nothnig
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    (Original post by bla_bla_bla_blaa)
    electronegativity is the ability to attract bonding electrons from an atom

    true or false? correct answer wins a rep worth nothnig
    Electronegativity is the degree to which an atom attracts electrons.

    Fluorine attracts more of the electron cloud, and so is more electronegative and will have a partial negative charge.
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    (Original post by Jamesrb)
    Electronegativity is the degree to which an atom attracts electrons.

    Fluorine attracts more of the electron cloud, and so is more electronegative and will have a partial negative charge.
    thanks..

    teaching is learning guys so help me to help you..

    why are chlorine radicals not produced from the break down chloromethane molecules in the trophosphere (whatever the hell that is)
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    if you get a question where you're given the concentration (in moldm^3) and volume in cm^3, do you multiply them then divide by 1000 to get moles?

    or do you divide by 1000 when you are given volume in dm^3?
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    (Original post by bla_bla_bla_blaa)
    if you get a question where you're given the concentration (in moldm^3) and volume in cm^3, do you multiply them then divide by 1000 to get moles?

    or do you divide by 1000 when you are given volume in dm^3?
    You always work out titrations in dm^3. 1000cm=1dm
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    No you dont all the guides say to do it in cm3
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    (Original post by bla_bla_bla_blaa)
    thanks..

    teaching is learning guys so help me to help you..

    why are chlorine radicals not produced from the break down chloromethane molecules in the trophosphere (whatever the hell that is)
    If they are broken down they are. However things are rarely broken down in the troposphere - most of the high frequency solar radiation required to break down the halogenoalkane has been absorbed by the ozone layer in the stratosphere (the stratosphere is above the troposhere).
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    (Original post by Moe Lester)
    You always work out titrations in dm^3. 1000cm=1dm
    ite..

    and how many electrons does sodium have in its outershell

    rofl jk man relax
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    (Original post by Dukedom)
    No you dont all the guides say to do it in cm3
    No, you convert to dm^3. The concentration is given as mol dm-3 or g dm-3, at some point you have to convert to dm.
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    (Original post by bla_bla_bla_blaa)
    ite..

    and how many electrons does sodium have in its outershell

    rofl jk man relax
    Relax? Why are you asking questions if you don't want them answered?
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    Lower frequency of radiation and therefore energy in the troposphere... God knows why ! Any help here... haha


    Are the following 2 statements true :

    1) Ionisation enthalpy decreases down the group, and therefore reactivity increases

    2) Methane is useful in the stratopshere as it removes chlorine radicals which cause depletion of ozone. Howere in the troposphere it is less useful as ozone is harmful in the troposphere and therefore we want it to be removed form Cl radicals, but the methane causes them to dissappear.

    Sorry that was worded terribly :P

    Also does anyone know how to draw a NO or NO2 radical :O ? =]
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    (Original post by rainbowsss)
    Lower frequency of radiation and therefore energy in the troposphere... God knows why ! Any help here... haha
    Because it's already been absorbed by the ozone layer present in the stratosphere?

    Are the following 2 statements true :

    1) Ionisation enthalpy decreases down the group, and therefore reactivity increases
    No, electronegativity - although that links with ionisation enthlapy. Reactivity increases up groups.

    2) Methane is useful in the stratopshere as it removes chlorine radicals which cause depletion of ozone. Howere in the troposphere it is less useful as ozone is harmful in the troposphere and therefore we want it to be removed form Cl radicals, but the methane causes them to dissappear.


    Sorry that was worded terribly :P

    Also does anyone know how to draw a NO or NO2 radical :O ?
    Well you just draw NO or NO2. making sure it has one unpaired electron.
 
 
 
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