question_answer 13)

Which one of the following has the highest dipole moment?  (i)                          (ii)                             (iii)  

Answer:

                                              (i)  (tetrachloromethane) is a symmetrical molecule so, it haszero dipole moment. (ii) In  (trichloromethane/chloroform), the resultant of twoC?CI dipole moments is opposed by the resultant of C?H andC?CI bond. Since, the latter resultant dipole moment is smallerthan the former,  has a dipole moment = 1.03 D. (iii) In  (dichloromethane), the resultant of two C?CI dipolemoments is reinforced by the resultant of two C?H bonds. Thus, has a dipole moment = 1.62 D. Therefore,  has the highest dipole moment amongst theabove three molecules. Note is also called carbon, tetrachloride;  is methylene chloride.