What are X and Y?

A C8H14 hydrocarbon (X) is reduced by sodium in liquid ammonia to a single C8H16 product (Y). Both of these compounds undergo hydrogenation (Pt catalyst) to give 2,5-dimethylhexane. Ozonolysis of Y with an oxidative workup produces a single C4H8O2 carboxylic acid. Reaction of Y with perbenzoic acid (C6H5CO3H) gives a chiral C8H14O product, but reaction with bromine gives an achiral C8H14Br2 product.