JEE Main & Advanced Chemistry The Solid State / ठोस प्रावस्था Question Bank Mock Test - Solid State

  • question_answer
    If NaCl is doped with \[{{10}^{-3}}\] mole% of \[SrC{{l}_{2}}\], the number of cationic vacancies is

    A) \[6.02\times {{10}^{-18}}mo{{l}^{-1}}\]

    B) \[{{10}^{-5}}mo{{l}^{-1}}\]

    C) \[6.02\times {{10}^{20}}mo{{l}^{-1}}\]

    D) \[6.02\times {{10}^{18}}mo{{l}^{-1}}\]

    Correct Answer: D

    Solution :

    [d] Due to the addition of\[SrC{{l}_{2}}\], each \[S{{r}^{2+}}\]ion replaces two \[N{{A}^{+}}\]ions, but occupies one \[N{{A}^{+}}\]lattice point. Thus, this exchange of \[N{{a}^{+}}\]ion by \[S{{r}^{2+}}\]ion makes one cationic vacancy. \[SrC{{l}_{2}}\]doped\[={{10}^{-3}}\]mol per 100 mol \[={{10}^{-5}}\]mol per 1 mol \[\therefore \]Cation vacancies \[={{10}^{-5}}\]mol per 1 mol \[={{10}^{-5}}\times {{N}_{A}}mo{{l}^{-1}}={{10}^{-5}}\times 6.02\times {{10}^{23}}\] Total \[=6.02\times {{10}^{18}}\]cationic vacancies \[mo{{l}^{-1}}\]


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