In acidic medium, dichromate ion oxidizes ferrous ion to ferric ion. If the gram molecular weight of potassium dichromate is ` 294 g`, is gram equivalent weight is `"______" g`.A. ` 294`B. ` 127`C. `49`D. ` 24.5`

In acidic medium, dichromate ion oxidizes ferrous ion to ferric ion. I

1.	In acidic medium, dichromate ion oxidizes ferrous ion to ferric ion. If the gram molecular weight of potassium dichromate is ` 294 g`, is gram equivalent weight is `"______" g`.A. ` 294`B. ` 127`C. `49`D. ` 24.5`
Answer» Correct Answer - C Equivalent mass of oxidizing agent `=("Formula mass")/(("Total change in oxidation number of element"),("oxidized or reduced per mole of compound"))` `overset(+6)(C)r_(2)O_(7)^(2-) rarr 2overset(+3)(C)r^(3+)` The total change in oxidation number (For two Cr atoms ) is of ` 6 ` units ( +12 to 6 ). Thus, Equvalent mass `= (296)/6 = 49` Here students often make the mistake of dividing formula mass by 3 as they calculate the change in oxidation number for just one Cr atom.

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In acidic medium, dichromate ion oxidizes ferrous ion to ferric ion. If the gram molecular weight of potassium dichromate is ` 294 g`, is gram equivalent weight is `"______" g`.A. ` 294`B. ` 127`C. `49`D. ` 24.5`

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