Substitution and Addition Mechanism - Substitution Reactions (9.1) Flashcards
Nucleophilic Substitution takes place mainly with haloalkanes. True or False?
True
Which molecule is used to test for halide ions?
Silver Nitrate (AgNO3)
In nucleophilic substitution a nucleophile is added to the molecule. True or False?
True
Another haloalkane is eliminated in nucleophilic substitiution. True or False?
False - a ion or molecule is eliminated.
Define an SN2 reaction.
- Has 2 species in the rate determining step.
- Takes place with primary haloalkanes.
Define an SN1 reaction.
- 1 species in the rate determining step.
- Takes place with tertiary haloalkanes.
What does Markonikov’s Rule state?
- most stable carbocation intermediate = one with most alkyl groups substituted.
- mechanism with proceed through most stable intermediate
What does Markonikov’s rule state about order of stability?
A tertiary carbocation is more stable than a secondary and primary carbocation.
Why do tertiary haloalkanes undergo SN1 reactions?
- tertiary carbonations = most stable
- 3 bulky alkyl chains prevents nucleophile from attacking halide bonded carbon
Why do primary alkanes undergo SN2 reactions?
- primary carbocations = the least stable
- nucleophile can attack the halide bonded carbon, without hinderance from bulky alkyl group.
Secondary haloalkanes undergo a mixture of SN1 & SN2 reactions. True or False?
True - as they are in the middle of being stable and non-stable.
Which element makes the strongest bonds with carbon?
Fluorine
Bromine makes the weakest bonds with carbon. True or False?
False - Iodine makes the weakest bonds as it is the least electronegative out of the halogens.
Iodine is the best leaving group out of the halogens. True or False?
True
Why are larger halide ions more stable?
- -ve charge = distributed over a greater surface area.
