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    (Original post by C0balt)
    You mean UVbreaks Cl-Cl bond

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    Yeah 😊.
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    Can someone explain the conditions for nucleophillic substitution and elimination reactions.

    With nucleophillic is it in water and in eliminated in ethanol. How come primary alcohols favour nucleophillic and tertiary elimination. If I remember correctly?
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    (Original post by Super199)
    Can someone explain the conditions for nucleophillic substitution and elimination reactions.

    With nucleophillic is it in water and in eliminated in ethanol. How come primary alcohols favour nucleophillic and tertiary elimination. If I remember correctly?
    In alcoholic condition the OH acts as a base
    In aqueous (a bit of ethanol as solvent though) OH acts as a nucleophile
    Do you mean tertiary prefer SN1 and primary prefer SN2 in nucleophilic substitution?
    For tertiary there is steric hinderance so it favours the SN1

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    (Original post by C0balt)
    In alcoholic condition the OH acts as a base
    In aqueous (a bit of ethanol as solvent though) OH acts as a nucleophile
    Do you mean tertiary prefer SN1 and primary prefer SN2 in nucleophilic substitution?
    For tertiary there is steric hinderance so it favours the SN1

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    What is SN1 and SN2. And sorry I didn't mean alcohols, it is it late forgive me
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    (Original post by Super199)
    What is SN1 and SN2. And sorry I didn't mean alcohols, it is it late forgive me
    Idk if it's in your syllabus (im Edexcel) but they are different mechanisms for nucleophilic substitution of halogenoalkane with aqueous sodium hydroxide

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    (Original post by C0balt)
    Idk if it's in your syllabus (im Edexcel) but they are different mechanisms for nucleophilic substitution of halogenoalkane with aqueous sodium hydroxide

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    Na it isn't Edexcel is **** exam board for Chemistry isn't it?
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    (Original post by Super199)
    Na it isn't Edexcel is **** exam board for Chemistry isn't it?
    What exam board? on previous pages I've posted the mechanisms for OCR
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    (Original post by S.Ahmad)
    Nucleophilic Substitution:

    -The halogen is more electronegative than the Carbon atom and so becomes slightly negative, which induces the carbon atom to become slightly positively charged - electron deficient Carbon atom. This attracts nucleophiles such as OH. The lone pair of electrons from the nucleophile (formed due to heterolytic fission) are attracted and donated to the electron-deficient Carbon atom - this forms a new covalent bond between the Oxygen atom and Carbon atom. The C - Br breaks by heterolytic fission, and the electrons are donated to the halogen forming an ion.

    Electrophilic Addition:

    -This mechanism occurs during halogenation and halogenoalkane. The halogen is more electronegative and so becomes slightly negatively charged as the electron pair is attracted to the Bromine atom, this induces the Hydrogen atom to become slightly positively charged. The electron pair from the Carbon=Carbon is attracted by the slightly charged hydrogen atom which causes the double bond to break. A new bond forms between the first carbon atom and the hydrogen atom, and so the H - Br bond breaks by heterolytic fission and the electron pair goes to the bromine, forming a bromide (ion), which then reacts with the positively charged carbon atom.

    [P.S, sorry for the poor drawing]
    Here
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    (Original post by Super199)
    Na it isn't Edexcel is **** exam board for Chemistry isn't it?
    Oh Is It ? How come
    I don't have much to complain about Edexcel chemistry :confused:

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    (Original post by S.Ahmad)
    What exam board? on previous pages I've posted the mechanisms for OCR
    AQA
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    Can someone tell me the table for doing titrations.
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    Help!How would I name this alcohol? Can someone guide me through the process?
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    (Original post by C0balt)
    Oh Is It ? How come
    I don't have much to complain about Edexcel chemistry :confused:

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    C0balt and I are going to push the grade boundaries high lol
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    (Original post by frozo123)
    C0balt and I are going to push the grade boundaries high lol
    please dont
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    (Original post by SubwayLover1)
    I don't understand why it goes from 118 to 104.5 though?
    Ah if you have a molecule with 2 lone pairs and 2 bonding pairs then you should start off by comparing this to a molecule with 4 electron pairs.

    Now the maximum angle of a shape with 4 electron pairs is 109.5o.
    That's for a molecule with a tetrahedral structure (molecule with 4 bonding electrons).



    Now if you replace a bonding pair with a lone pair then you'll reduce the bond angle by 2.5o.

    Seeing as the molecule you're talking about has 2 bonding pairs and 2 lone pairs you should reduce the bond angle by 2 x 2.5o.

    109.5o - 5o = 104.5o

    Here's an example:


    I hope that helps
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    (Original post by Disney0702)
    Ah if you have a molecule with 2 lone pairs and 2 bonding pairs then you should start off by comparing this to a molecule with 4 electron pairs.

    Now the maximum angle of a shape with 4 electron pairs is 109.5o.
    That's for a molecule with a tetrahedral structure (molecule with 4 bonding electrons).



    Now if you replace a bonding pair with a lone pair then you'll reduce the bond angle by 2.5o.

    Seeing as the molecule you're talking about has 2 bonding pairs and 2 lone pairs you should reduce the bond angle by 2 x 2.5o.

    109.5o - 5o = 104.5o

    Here's an example:


    I hope that helps
    Wow!
    I get it now!!
    Thank-you so much!!!!
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    Just for some help for you guys out there for the AS Exams:
    remember to use the atomic mass to work out Molar Masses this is very important
    In Mass spectrometry, you always remember the molecule which is the lightest gets deflected the least!
    Moles= Molar Mass/ Mass
    Moles= concentration/volume x1000
    Electrophilic addition reactions occur with Halogenoalkanes and you get two products
    Hydrogen bonding is the weakest intermolecular force

    Hope that helps
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    (Original post by frozo123)
    Just for some help for you guys out there for the AS Exams:
    remember to use the atomic mass to work out Molar Masses this is very important
    In Mass spectrometry, you always remember the molecule which is the lightest gets deflected the least!
    Moles= Molar Mass/ Mass
    Moles= concentration/volume x1000
    Electrophilic addition reactions occur with Halogenoalkanes and you get two products
    Hydrogen bonding is the weakest intermolecular force

    Hope that helps
    Thanks for the top tips! :evil:
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    (Original post by Kadak)
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    Help!How would I name this alcohol? Can someone guide me through the process?
    its 3-ethyl-2-methylpentane-1,5-diol

    you count from the OH group because their the most important functional group, and you name the branches in alphabetical order, E coming before M

    hope this helps
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    (Original post by ThatMadClown)
    its 3-ethyl-2-methylpentane-1,5-diol

    you count from the OH group because their the most important functional group, and you name the branches in alphabetical order, E coming before M

    hope this helps


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    Yes it did! Ty!
 
 
 
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