Compound W, C8H17Br, and X, C8H17Cl, are products of the radical bromination (W), and chlorination (X), of 2,4-dimethylhexane. W and X are each chiral. W reacts readily in water to form a chiral substitution product Y, C8H17OH. Reaction of a single enantiomer of W produces a single enantiomer of Y as the only substitution product. X likewise reacts readily in water though at a slower rate than W; a chiral substitution product Z, C8H17OH, is again formed. Unlike W, however, reaction of a single enantiomer of X produces Z that is nearly racemic. Propose structures for W and X.