[starter]

For the Reaction:

Cl- + 2-iodo-2-methyl-butane = 2-chloro-2-methyl-butane + HI

ok i have to figure out which one of these affects the rate of the reaction. I dont understand where the H comes from for the HI. Im just confused is this a Sn1 reaction because thats the only way the iodine would leave without distorting the shape of 2-chloro-2-methyl-butane. I really dont know what my guess would be that the Cl- and the 2-iodo-2-methyl-butane control the rate of reaction. Any help would be nice thanks in advance.

[azmanam]

First, check your reaction again.  The left side of the arrow has a net (-1) charge, and the right side of the arrow has a net (0) charge.  Something's missing.  Perhaps the starting material on the left is supposed to be HCl?

the only way the iodine would leave without distorting the shape of 2-chloro-2-methyl-butane

What do you mean by 'distorting the shape'?

See here for some background:
http://www.cem.msu.edu/~reusch/VirtTxtJml/alhalrx3.htm#hal9

If your guess is S_N1, do you know what 'S_N1' stands for?  It's an acronym.  see here for hints:
http://www.cem.msu.edu/~reusch/VirtTxtJml/alhalrx2.htm

Knowing what S_N1 and S_N2 (as well as E1 and E2) stand for will help in determining which compounds affect the reaction rate, that is, it will help in determining which compounds show up in a rate law: k[A]^m(B)ⁿ[C]^o...

{edited to fix link, grammar, and formatting.  (B) because brackets format the text as bold...}