EAMCET Medical EAMCET Medical Solved Paper-1998

  • question_answer
    The radii of \[\text{F,}{{\text{F}}^{-}}\text{O}\]and\[{{\text{O}}^{2-}}\] are in the order

    A)  \[{{O}^{2-}}>{{F}^{-}}>O>F\]    

    B)  \[{{O}^{2-}}>{{F}^{-}}>F>O\]

    C)  \[{{F}^{2-}}>{{O}^{2-}}>F>O\]  

    D)  \[{{O}^{2-}}>O>{{F}^{-}}>F\]

    Correct Answer: A

    Solution :

                     Note: In a period from left to right, as the atomic number increases, atomic radii decreases. Therefore, in F and O, oxygen has higher value of atomic radii than fluorine. \[\text{Radii}\propto \frac{\text{1}}{\text{Effective}\,\text{nuclear}\,\text{charge}}\] Hence, anions have bigger size than parent atom as the effective nuclear charge decrease by increasing the -ve charge. So, \[{{\text{O}}^{2-}}\]has greater size than \[{{\text{F}}^{-}}\] Thus, the correct order is: \[{{O}^{2-}}<{{F}^{-}}>O>F\]


You need to login to perform this action.
You will be redirected in 3 sec spinner