How many grams of potassium dichromate are required to oxidise 20.0 g of Fe^(2+) in FeSO_4 " to " Fe^(3+) if the reaction is carried out in an acidic solution ?

How many grams of potassium dichromate are required to oxidise 20.0 g

1.	How many grams of potassium dichromate are required to oxidise 20.0 g of Fe^(2+) in FeSO_4 " to " Fe^(3+) if the reaction is carried out in an acidic solution ?
Answer» SOLUTION :When dissolved in water , `K_2Cr_2O_7` dissociates into `K^+ and Cr_2O_7^(2-)` ions and `FeSO_4` dissociates into `FE^(2+) and SO_4^(2+)` ions. The skeleton EQUATION is : `Fe^(2+) + Cr_2O_7^(2-) rarr Fe^(3+) +2Cr^(3+)` The BALANCED equation is `Cr_2O_7^(2-)+6FE^(2+)+14H^(+)rarr6Fe^(3+)+2Cr^(3+)+7H_2O` Formula weight of `K_2Cr_2O_7=2xx39+2xx52+7xx16=294` Formula weight of `FeSO_4` `=56+32+4xx16=152` `:.` 1 mol `K_2Cr_2O_7=6 mol FeSO_4` `294 ""6xx152` `6xx152` g of `FeSO_4` require `K_2Cr_2O_7 = 294 g` 20 g of `FeSO_4` require `K_2Cr_2O_7` `=(294)xx(6xx152)xx20=6.45g` `K_2Cr_2O_7` required to oxidise 20 g of `FeSO_4` `=6.45 g `