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Sn1 Sn2 Substitutions




Sn1 is a two stage process, the halogen ion drops off, later the hydroxide ion is added    





+ OH -   


2) What does the S in Sn1 stand for?  
3) What does the n in Sn1 stand for?  

Sn2 is a one stage process, as the hydroxide ion approached the halogen ion leaves (yes, I know it looks like 2 steps)



+ OH-


+ Br-
4) Name the chemical below.    
5) Why would an OH- ion approach a carbon on this molecule?

6) Which bromide ion undergoes Sn1?  
7) A primary haloalkane site has a halogen atom attached to a carbon AND this carbon is only attached to one other carbon.  Which bromide represents a primary haloalkane site? left
8) Rate =[BrC(CH3)CH2CH2Br] for an Sn1 reaction.  Which bromide is this (again)? left
9) Explain why the overall rate is first order.


10) Rate =[BrC(CH3)CH2CH2Br][] for an Sn2 reaction since the slowest (and only) equation has 2 chemicals present.  This is what happens to tertiary haloalkanes.    
11) How do secondary haloalkanes behave (halogen atom attached to a carbon AND this carbon is only attached to two other carbons). Sn1
Sn1 and Sn2
12) Since this molecule is a primary alkane it will undergo Sn2.  Which haloalkane will be substituted and why?

13) Sn2 is normally slower than Sn1 because

14) Comments: