Question

volume of 0.1M K2Cr2O7 required to oxidise 35ml of 0.5M FeSO4 solution is

Answer 1

Potassium dichromate (K2Cr2O7) react with iron(II) sulfate (FeSO4) in the presence of sulfuric acid to produce chromium(III) sulfate (Cr2(SO4)3), iron(III) sulfate (Fe2(SO4)3), potassium sulfate (K2SO4) and water (H2O).

The chemical equation is:


K2Cr2O7 + 6FeSO4 + 7H2SO4 → Cr2(SO4)3 + 3Fe2(SO4)3 + K2SO4 + 7H2O


Moles of FeSO4 in 35ml of 0.5M FeSO4 solution = (35/1000) * 0.5 = 0.0175



According to the equation:

6 moles of FeSO4 require 1 mole of K2Cr2O7

0.0175 moles will require = (0.0175x1)/6


                                         = 0.002917 moles of K2Cr2O7



Volume =  Number of moles/Molarity


Volume of K2Cr2O7 = 0.002917/0.1 = 0.02917 Litres



Volume = 0.02917 x 1000 ml


             = 29.17 ml

Answer 2

Answer:

Explanation:

Potassium dichromate (K2Cr2O7) react with iron(II) sulfate (FeSO4) in the presence of sulfuric acid to produce chromium(III) sulfate (Cr2(SO4)3), iron(III) sulfate (Fe2(SO4)3), potassium sulfate (K2SO4) and water (H2O).

The chemical equation is:

K2Cr2O7 + 6FeSO4 + 7H2SO4 → Cr2(SO4)3 + 3Fe2(SO4)3 + K2SO4 + 7H2O

Moles of FeSO4 in 35ml of 0.5M FeSO4 solution = (35/1000) * 0.5 = 0.0175

According to the equation:

6 moles of FeSO4 require 1 mole of K2Cr2O7

0.0175 moles will require = (0.0175x1)/6

= 0.002917 moles of K2Cr2O7

Volume = Number of moles/Molarity

Volume of K2Cr2O7 = 0.002917/0.1 = 0.02917 Litres

Volume = 0.02917 x 1000 ml

= 29.17 ml