Turn on thread page Beta
    • Thread Starter
    Offline

    0
    ReputationRep:
    According to my text book the reaction type of an alkene reacting with a halogen molecule is an "electrophillic addition" reaction but when an alkene reacts with a hydrogen molecule they say its an "addition" reaction.

    Why is this? Is hydrogen not an electrophille?
    Offline

    0
    ReputationRep:
    Standard reactions with alkenes are electrophilic addition due to the high electron density surrounding the carbon double bond.

    As with other reactions you will have to learn about in due course, "hydrogen" reactions are slightly different because it is hydrogen being reacted.

    Hydrogen, for the sake your understanding, can be assumed to be a nucleophile but the reaction is called something else: Catalytic Hydrogenation.

    You can only add hydrogen across a double bond with the presence of a Nickel catalyst.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by Mastahh)
    Standard reactions with alkenes are electrophilic addition due to the high electron density surrounding the carbon double bond.

    As with other reactions you will have to learn about in due course, "hydrogen" reactions are slightly different because it is hydrogen being reacted.

    Hydrogen, for the sake your understanding, can be assumed to be a nucleophile but the reaction is called something else: Catalytic Hydrogenation.

    You can only add hydrogen across a double bond with the presence of a Nickel catalyst.
    It then goes on to say that in H-Br, hydrogen is an electrophille?:confused:
    Offline

    0
    ReputationRep:
    (Original post by polaritymolecule)
    It then goes on to say that in H-Br, hydrogen is an electrophille?:confused:
    Yes it does. Hydrogen is a partially positive atom in that molecule that is attracted to the electron density.
    Offline

    16
    ReputationRep:
    (Original post by Mastahh)
    You can only add hydrogen across a double bond with the presence of a Nickel catalyst.
    There are many, many catalysts which will do the job, it is not limited to Nickel.
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: January 2, 2013
Poll
Do you think parents should charge rent?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.