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    (Original post by AlphaWolfZ)
    Quick question y'all, about halogen displacement visualisations. When in a displacement reaction, and I2 is produced. What is the color change? I'm getting conflicting results, is it brown or deep purple? Isn't the color of iodine dark grey, so shouldnt it be grey?
    I think its usually due to the state of the halogen. I2 is browny yellow in solution and grey black as a solid and purple as a gas

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    How would you name: CH3-NH-CH(CH3)2
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    Can someone go over hydration reations quickly because I dont understand the mechanism
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    Can someone list all of the mechanisms we need to know?
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    (Original post by shiney101)
    How would you name: CH3-NH-CH(CH3)2
    Let me take a guess.

    N-methylpropan-2-amine.

    Oh yeaaah look at that http://www.chemexper.com/chemicals/s...4747-21-1.html.
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    Free radical substitution
    Nucleophilic substitution
    Electrophilic addition
    Elimination (dehydration)
    Elimination
    Acid catalysed addition
    I think that's it!
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    (Original post by Anna1909)
    Free radical substitution
    Nucleophilic substitution
    Electrophilic addition
    Elimination (dehydration)
    Elimination
    Acid catalysed addition
    I think that's it!
    Is this everything or have I missed something? ASMechanisms.pdf
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    (Original post by voltz)
    Can someone go over hydration reations quickly because I dont understand the mechanism
    Post 74 gives a summary of hydration.

    http://www.thestudentroom.co.uk/show...4148507&page=4
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    Can anyone give me a brief rundown of a hydrogen fuel cell? What advantages does it have over an ethanol fuel cell?
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    Colour changes for methyl orange and phenolphtalein ?
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    (Original post by Kadak)
    Colour changes for methyl orange and phenolphtalein ?
    I know that phenolphthalein goes from colourless to pink when alkaline is added.
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    (Original post by Kadak)
    Colour changes for methyl orange
    Orangey/red to yellow.

    (Original post by Kadak)
    and phenolphtalein ?
    Colourless to pink.

    ^

    In acidic conditions, I think.
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    (Original post by Avocado2002)
    Is this everything or have I missed something? ASMechanisms.pdf
    Hydration?
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    (Original post by EricPiphany)
    I know that phenolphthalein goes from colourless to pink when alkaline is added.
    Ty.
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    (Original post by Anon_98)
    Orangey/red to yellow.



    Colourless to pink.

    ^

    In acidic conditions, I think.
    Thank you .
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    Could someone explain why NO2 groups are electron withdrawing? Im struggling to understand the chemistry behind it.

    Thank you in advance
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    (Original post by ayvaak)
    Could someone explain why NO2 groups are electron withdrawing? Im struggling to understand the chemistry behind it.

    Thank you in advance
    Draw resonance forms. You can push an electron from N=O to O, etc.
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    (Original post by alow)
    Draw resonance forms. You can push an electron from N=O to O, etc.
    Im not sure i fully understand. The quote something i read online.

    "Electron withdrawing groups (EWG) with p bonds to electronegative atoms (e.g. -C=O, -NO2) adjacent to the p system deactivate the aromatic ring by decreasing the electron density on the ring through a resonance withdrawing effect. The resonance only decreases the electron density at the ortho- and para- positions. Hence these sites are less nucleophilic, and so the system tends to react with electrophiles at the meta sites."

    The underlined is what i dont seem to understand? How can removing electron density from benzene ring make it less nucleophilic rather than less electrophillic?
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    (Original post by ayvaak)
    Im not sure i fully understand. The quote something i read online.

    "Electron withdrawing groups (EWG) with p bonds to electronegative atoms (e.g. -C=O, -NO2) adjacent to the p system deactivate the aromatic ring by decreasing the electron density on the ring through a resonance withdrawing effect. The resonance only decreases the electron density at the ortho- and para- positions. Hence these sites are less nucleophilic, and so the system tends to react with electrophiles at the meta sites."

    The underlined is what i dont seem to understand? How can removing electron density from benzene ring make it less nucleophilic rather than less electrophillic?
    Do you know what a resonance form is?
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    Name:  image.jpg
Views: 67
Size:  291.7 KBCan someone explain how to derive the answer for this kind of a question. How can we differentiate the pH of molecules based off their molecular formulae?
 
 
 
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