question_answer

 The correct order of basic strength of the following are         

A)  \[{{10}^{-4}}\,M\,C{{a}^{2+}}+{{10}^{-4}}M{{F}^{-}}\]                   

B)  \[{{10}^{-2}}\,M\,C{{a}^{2+}}+{{10}^{-3}}M{{F}^{-}}\]

C)  \[2{{H}^{+}}+2{{e}^{-}}+\frac{1}{2}{{O}_{2}}\xrightarrow{{}}{{H}_{2}}O(l);{{E}^{o}}=+1.23V\]    

D)   \[F{{e}^{2+}}+2{{e}^{-}}\xrightarrow{{}}Fe(s);\,\,{{E}^{o}}=-0.44V\]

Correct Answer: D

Solution :

                Electron releasing groups increase the basic strength   of   amines   whereas   electron withdrawing groups decrease it. Therefore, III > II > IV > I, since in                 \[III<IV<I<II\] group is planked between two electron withdrawing groups.