Sentence:  Related to micelle formation is the technologically important ability of detergent actives to congregate at oil water interfaces in such a manner that the polar ( or ionized ) end of the <WSD>molecule</WSD> is directed towards the aqueous phase and the hydrocarbon chain towards the oily phase . 
Meaning of the word marked with <WSD> tags:  (physics and chemistry) the simplest structural unit of an element or compound