contestada

The average human body contains 5.00 L of blood with a Fe2+ concentration of 1.10×10−5 M . If a person ingests 9.00 mL of 21.0 mM NaCN, what percentage of iron(II) in the blood would be sequestered by the cyanide ion?

Respuesta :

Answer:

The  percentage is    % [tex]Fe^{2+[/tex]   [tex]= 57.3[/tex]%

Explanation:

From the question we are told that  

       The volume of blood in the human body  is  [tex]V = 5.0 0 \ L[/tex]

       The  concentration of  [tex]Fe^{2+[/tex] is  [tex]C_{F} = 1.10 *10^{-5} \ M[/tex]

        The volume  of  NaCN  ingested is  [tex]V_N = 9.00 \ mL = 9.00 *10^{-3} \ L[/tex]

       The concentration of  NaCN ingested is  [tex]C_N = 21.0 \ mM = 21.0 *10^{-3} \ M[/tex]

The  number of moles of   [tex]Fe^{2+[/tex] in the blood is  

                    [tex]N_F = C_F * V[/tex]

substituting values  

                    [tex]N_F = 1.10 *10^{-5} * 5[/tex]

                    [tex]N_F = 5.5*10^{-5} \ mols[/tex]

The  number of moles of  [tex]CN^{-}[/tex] ingested is  mathematically evaluated as

           [tex]N_C = C_N * V_N[/tex]

substituting values    

          [tex]N_C = 21*10^{-3} * 9 *10^{-3}[/tex]

          [tex]N_C = 1.89 *10^{-4} \ mols[/tex]

The balanced chemical equation for the reaction  between   [tex]Fe^{2+[/tex] and   [tex]CN^{-}[/tex]  is  represented as

          [tex]Fe^{2+} + 6 CN^{-} \to [Fe(CN)_6]^{2-}[/tex]

From this  reaction we see that  

         1 mole  of    [tex]Fe^{2+[/tex]  will react with 6  moles of  [tex]CN^{-}[/tex]

=>         x  moles of  [tex]Fe^{2+[/tex] will react with   [tex]1.89 *10^{-4} \ moles[/tex] of  [tex]CN^{-}[/tex]

Thus  

         [tex]x = \frac{1.89 *10^{-4} * 1}{6}[/tex]

        [tex]x = 3.15 *10^{-5}[/tex]

Hence the percentage  of  [tex]Fe^{2+[/tex]  that reacted is  mathematically evaluated as

       

       %  [tex]Fe^{2+[/tex]   [tex]= \frac{3.15 *10^{-5}}{5.5*10^{-5}} * 100[/tex]

        %  [tex]Fe^{2+[/tex]   [tex]= 57.3[/tex]%