Answer:
See answer below
Explanation:
To understand this, we need to make the reaction involved with the given configuration. Configuration R means that the substituents of the molecule, the priority order goes clockwise (From heaviest to lightest) so, if an Sn2 is ocurring in the reaction this means that the nucleophile, which in this case, is the sodium ethoxide will attack the molecule in the opposite side of the leaving group (which is the chlorine).
Also when this occurs, as Sn2 is a bimolecular reaction and is held in one step, it occurs an inversion in the configuration of the product. So, it's the innitial reactant was R, then the final product will be S.
The mechanism and product can be watched in the attached picture
Hope this helps.
