What are Enantiomers?

The stereoisomers which are related to each other as non-superimposable mirror images are known as enantiomers. Enantiomers have similar physical properties such as boiling point, melting point, refractive index, etc. They only differ w.r.t the rotation of plane-polarized light. If one of the enantiomers is levorotatory, the other will be dextrorotatory. The compounds A and B in the following image are enantiomers.

Explain why alkyl halides, though polar, are immiscible with water?

To be miscible with water, the solute-water force of attraction must be stronger than the solute-solute and water-water forces of attraction. Alkyl halides are polar molecules and so held together by dipole-dipole interactions. Similarly, strong -bonds exist between the water molecules. The new force of attraction between the alkyl halides and water molecules is weaker than the alkyl halide-alkyl halide and water-water forces of attraction. Hence, alkyl halides (though polar) are immiscible with water.