A steel sample is to be analysed for Cr and Mn simultaneously . By suitable treatement Cr is oxidized as `Cr_(2)O_(7)^(2-)` and the Mn to `MnO_(4)^(-)`
`Cr rarr Cr_(2) O_(7)^(2-)`
`Mn rarr MnO_(4)^(-)`
A 10 gm sample of steel is used to produce 250.0 mL of a solution containing `Cr_(2)O_(7)^(2-)` and `MnO_(4)^(-)`. A 10mL portion of this solution is addedto a `BaCl_(2)` solution and by proper adjustment of the acidicty , the chromum is completely precipitated as `BaCrO_(4)` 0.0549 g is obtained.
`Cr_(2) O_(7)^(2-) overset( H^(o+))(rarr)BaCrO_(4)`
A second 10mL portion of this solution requires exactly 15.95mL of 0.0750 M standard `Fe^(3+)` solution for its titration ( in acid solution ) .
Amount of `BaCl_(2) ` required for conversion of `Cr_(2)O_(7)^(2-)` to `BaCrO_(4)` in steel sample .

Options

A. 0.045
B. 0.0549
C. 1.125
D. 2.82

Answer

C