question_answer 1)

  Ionic species are stabilised by the dispersal of charge. Which of the following carboxylate ions is the most stable? (a) \[C{{H}_{3}}-\overset{\overset{\text{O}}{\mathop{\text{ }\!\!|\!\!\text{  }\!\!|\!\!\text{ }}}\,}{\mathop{C}}\,-{{O}^{-}}\] (b) \[Cl-C{{H}_{2}}-\overset{\overset{\text{O}}{\mathop{\text{ }\!\!|\!\!\text{  }\!\!|\!\!\text{ }}}\,}{\mathop{C}}\,-{{O}^{-}}\]                (c) \[F-C{{H}_{2}}-\overset{\overset{\text{O}}{\mathop{\text{ }\!\!|\!\!\text{  }\!\!|\!\!\text{ }}}\,}{\mathop{C}}\,-{{O}^{-}}\]                (d)  

Answer:

  (d) Since F (two atoms) has the highest electro negativity, therefore dispersal of \[-ve\]charge is maximum in (d).