Answer
The bromide is a better leaving group
Work Step by Step
1. Identify the possibles leaving groups:
- $Bromide$ ($Br^-$)
- $Chloride$ ($Cl^-$)
2. Determine which one is better.
- We have learned that $Br^-$ is a good leaving group (page 218).
- And we have also learned that, the $Cl^-$ is also, a good leaving group (page 218).
But, if we analyze the image on page 218, we will see that, $Br^-$ is more stable than $Cl^-$, therefore, bromide is a better leaving group.
