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    Hey can some1 help me by telling me the conditions and reagents required to go from benzene to cyclohexane? thanks.
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    300C 30atm finely divided nickel catalyst and Hydrogen

    (I think)
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    ok cheers
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    (Original post by kohlstream)
    300C 30atm finely divided nickel catalyst and Hydrogen

    (I think)
    you sure? I thought Benzene couldnt undergo addition reactions
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    (Original post by Mathemagician)
    you sure? I thought Benzene couldnt undergo addition reactions
    Because of the high activation energy - the reason benzene is so stable is because of it's conjugated system (the delocalised electrons) in the pi-bonding system.
    If you take, eg the Friedel Crafts reactions, one of steps is a sort of addition into the ring. The C-H bond then breaks to replenish the electrons in the ring to maintain the stability.
    To overcome the high activation energy needed to disrupt the pi-bonding system you use a catalyst - Ni(s) and a high temp - 300C
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    By any chance, can you use platinum as a catalyst as well? I know you you can use it for making an alkene to an alkane at 1 atm and room temp, but is it the same coniditons for benzene?
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    No - hydrogenation of alkenes is H2(g), 180C, Ni(s) catalyst electrophilic addition
    Platinum is used in car engines - Pt/Rh catalytic converter.

    Or at least that's what we were told :confused:
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    (Original post by kohlstream)
    300C 30atm finely divided nickel catalyst and Hydrogen

    (I think)

    Thats right for if your talking about salters, because some exam boards have different reagents, there might be afew ways this can happen
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    (Original post by corkskrew)
    No - hydrogenation of alkenes is H2(g), 180C, Ni(s) catalyst electrophilic addition
    Platinum is used in car engines - Pt/Rh catalytic converter.

    Or at least that's what we were told :confused:

    The one I remember is platinum 1 atm, room temp cause its easy, but if they ask a question about cost effectiveness then i'm going to be buggered if i don't remember the nickel one.

    I think they tend not to teach the Platinum one, just because its not used as much in industry...

    I'm going to have to learn the nickel one...
 
 
 
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