Please write clearly so that I can’t understand what you are saying beter if it
ID: 543490 • Letter: P
Question
Please write clearly so that I can’t understand what you are saying beter if it is not in cursive leter thankyou. Explain why the reaction between octyl bromide and potassium iodide went to near completion (or at least should have), whereas the reaction of octyl bromide and potassium chloride did not approach anywhere near completion Which is a better nucleophile: KCI or KI? Explain using the key concepts polarizability and electronegativity of the nucleophiles. kci During the chromatography of the product of the SN2 reaction, what was removed from the solution?Explanation / Answer
1. The order of reactivity of halide leaving group in nucleophilic substitution reactions goes as
R-I > R-Br > R-Cl > R-F. From this we can understand that and I- is a better nucleophile than
Cl- hence I- tends to be more reactive than Cl- which is why the reaction goes to completion
when KI is used.
2. With increasing nucleophilicity, polarisation of the nucleophile keeps increasing as it increases the
ability to form the new bonds the order therefore will be, I- > Br- > Cl- > F-. Well, on electro-
negativity terms both of them have the same charge so it becomes difficult to judge basing
on this factor alone. Hence KI is better nucleophile.
3. The aqueous layer is removed and then chromatography is performed.