Nucleophilic Substitution (AS Chem)

Can anyone help me with these q's please:

1. When 1-bromopropane reacts with KOH, 2 different reactions can occur. For each of the reactions:
a) write an equation
b) name the organic product formed
c) outline the mechanism

2. What is the role of KOH in each reaction? (provides the nucleophile?)

3. What conditions may be employed to promote each reaction?

Thankyou.

anyone?

1) 1-bromopropane + KOH ----> Propan-1-ol + HBr Nucleophilic Substitution
_______________KOH
1-bromopropane ------> Propene + KBr + H20 Elimination

2)Provides Nucleophile for nucleophilic substitution in first and the Nucleophile (OH-) bonds and frees a Hydrogen atom from the molecule in the 2nd.

3) For first reaction cold water should be used as the solvent
For the 2nd, the reactants should be heated by reflux and the solvent should be ethanal.

Ooo thankyou We haven't done anything about elimination yet, so that would probably explain it! Thanks!

No problem I have edited sone of the answers slightly btw.

Do u want me to go into the mechanisms fully?

Erm if you could- on the elimination one - I already know the full mechanism for the substitution.

The exam boards like you to call the nucleophile a 'base' in the elimination reaction (although this seems stupid to me).

Ben

Erm if you could- on the elimination one - I already know the full mechanism for the substitution.

Cool, cus I didn't, #

Hope pic makes sense.

The OH- ion uses its lone pair to bond wid a Hydrogen. The old used to be electron pair from the C-H, forms part of a C=C bond. The Carbon bonded to thbe Bromine now has like 10 electrons in its outer shell, it sheds a pair of electrons with the electronegative Bromine atom, which becomes a Bromine Ion. Hence the halogenoalkane has re-emerged as an alkene!