A) \[2.6\times {{10}^{-9}}\]
B) \[4\times {{10}^{-8}}\]
C) \[8\times {{10}^{-12}}\]
D) \[3.2\times {{10}^{-11}}\]
Correct Answer: D
Solution :
Key Idea: Write reaction for dissociation of \[Ca{{F}_{2}}\] and then find relationship between \[{{K}_{sp}}\] and solubility. \[Ca{{F}_{2}}C{{a}^{2+}}+2{{F}^{-}}\] Given solubility of\[Ca{{F}_{2}}=2\times {{10}^{-4}}mol\,\,{{L}^{-1}}\] \[\therefore \] \[[C{{a}^{2+}}]=2\times {{10}^{-4}}mol\,\,{{L}^{-1}}\] \[[{{F}^{-}}]=2\times 2\times {{10}^{-4}}mol\,\,{{L}^{-1}}\] \[{{K}_{sp}}=[C{{a}^{2+}}]{{[{{F}^{-}}]}^{2}}\] \[=(2\times {{10}^{-4}}){{(2\times 2\times {{10}^{-4}})}^{2}}\] \[=32\times {{10}^{-12}}\] \[=3.2\times {{10}^{-11}}\]
You need to login to perform this action.
You will be redirected in
3 sec
