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    what is the general rule for the following reagents, as in when are suitable reagents?

    1. Sn/HCl 2. LiAlH4 2. NaBH4
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    (Original post by Anon_98)
    Yes, planning to but I've got quite a few exams next week so I'm worried I won't be able to fit it in.
    i see, in any case good luck.
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    (Original post by confusedkid1997)
    what is the general rule for the following reagents, as in when are suitable reagents?

    1. Sn/HCl 2. LiAlH4 2. NaBH4
    h2/ni for everything pretty much (its easiest to remember)
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    (Original post by confusedkid1997)
    what is the general rule for the following reagents, as in when are suitable reagents?

    1. Sn/HCl 2. LiAlH4 2. NaBH4
    Sn/HCl used for reducing nitrobenzene to aromatic amines
    LiAlH4 used for reducing nitriles to amines
    NaBH4 is only strong enough to reduce ketones and aldehydes to alcohols
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    (Original post by Hadigy)
    Page 123
    I get that the M+4 peak means there are 2 atoms of the halogen instead of one, but how does it change the ratio of the M and M+2 peak?? Do you thinkwe need to know that?
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    (Original post by Ultracrepidarian)
    i see, in any case good luck.
    Thank you v much, hopefully it'll work out- I'll tag you/something if I manage it.
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    Do we need to know about bond angles in benzene compared to the cyclo's
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    (Original post by Hadigy)
    Do we need to know about bond angles in benzene compared to the cyclo's
    Yes, bond angle in benzene is 120 compared to the cyclo which is 109.5
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    (Original post by thehollowcrown)
    Sn/HCl used for reducing nitrobenzene to aromatic amines
    LiAlH4 used for reducing nitriles to amines
    NaBH4 is only strong enough to reduce ketones and aldehydes to alcohols
    can i use H2/Ni for reducing nitriles?
    And thanks for the reply
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    (Original post by confusedkid1997)
    can i use H2/Ni for reducing nitriles?
    And thanks for the reply
    i belive you can
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    (Original post by Hadigy)
    Do we need to know about bond angles in benzene compared to the cyclo's
    Not for CHEM 4 we don't, we do need to know about bond strength and stability in benzene though and be able to compare it to cyclo. i.e explain why it is more stable.

    Good Luck
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    (Original post by confusedkid1997)
    can i use H2/Ni for reducing nitriles?
    And thanks for the reply
    Yeah, pretty sure it always has that in the mark scheme as well as LiAlH4
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    (Original post by Jackpalmer1996)
    Not for CHEM 4 we don't, we do need to know about bond strength and stability in benzene though and be able to compare it to cyclo. i.e explain why it is more stable.

    Good Luck
    they have asked a question comparing bond angles before
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    (Original post by Jackpalmer1996)
    Not for CHEM 4 we don't, we do need to know about bond strength and stability in benzene though and be able to compare it to cyclo. i.e explain why it is more stable.

    Good Luck
    you do, it came up a few years ago
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    (Original post by Kaya22)
    i belive you can
    If they ask for conditions they are high temp. and pressure as well.
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    (Original post by Kaya22)
    i belive you can
    thanks man , good luck
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    (Original post by Jpw1097)
    You would use the base dissociation constant, Kb, if there was an excess of a weak base. If there is an excess of a strong base, you just use Kw, to find [H+]. However, we are not tested on questions using Kb, it's either an excess of weak acid or an excess of a strong base.
    Ah ****, My bad people, i thought he was talking about buffers . and yes that right. In the case of buffer ive been told a few times that excess base to an acid, will has never come up, and that seems to be true.
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    Do we need to memorise the pH indicators and their pH ranges?
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    (Original post by vaishnagaraj)
    Do we need to memorise the pH indicators and their Ph ranges?
    nope
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    (Original post by vaishnagaraj)
    Do we need to memorise the pH indicators and their Ph ranges?
    you just need to know phenolphthalein and methyl orange
 
 
 
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