A 4.0 g sample contained `Fe_2O_3,Fe_3O_4`, and inert material. It was treated with an excess of aq KI solution in acidic medium, which reduced all iron to `Fe^(2+)` ions along with the liberation of iodine . The resulting solution was diluted to 50 mL and a 10 mL sample of it was taken the iodine liberated in the small sample was titrated with 12.0 " mL of " 0.5 M `Na_2S_2O_3` solution. The iodine from another 25 mL was extracted, after which the `Fe^(2+)` ions were titrated with 16 " mL of " 0.25 M `MnO_4^(ɵ)` ions in `H_2SO_4` solution. Calculate the mass of two oxides in the original mixture.

A 5g sample containing FeO_4 (FeO+Fe_2O_3) and an inert impurity is treated with excess of KI solution in the presence of dilute H_2SO_4 .The entire Iron converted to Ferrous ion along with liberation of Iodine.The resulting solution is diluted to 100 ml. 20 ml of the diluted solution requires 10 ml of 0.5M Na_2S_2O_3 solution to reduce the Iodine present.Amongs the following select correct statements.

A 3.00 g sample containing Fe_(3)O_(4), Fe_(2)O_(3) and an inert impure substance, is treated with excess of KI solution in presence of dilute H_(2)SO_(4) . The entire iron is converted into Fe^(2+) along with the liberation of iodine. The resulting solution is diluted to 100 mL. A 20 mL of the dilute solution requires 11.0 mL of 0.5 M Na_(2)S_(2)O_(3) solution to reduce the iodine, present. A 50 mL of the dilute solution after complete extraction of the iodine required 12.80 mL of 0.25 M KMnO_(4) solution in dilute H_(2)SO_(4) medium for the oxidation of Fe^(2+) . Calculate the % of Fe_(2)O_(3) "and" Fe_(3)O_(4) in the original sample.

Iodine is liberated from KI solution when treated with :

A sample of pure aniline was dissolved in HCl and diluted to 100 mL with H_2O . 20 " mL of " liquid was treated with 25 " mL of " 0.017 M KBrO_3 and about 10 g KBr was added to form Br_2 . After 10 min, an excess of KI was added and the liberated I_2 was titrated with 12.92 " mL of " 0.12 M Na_2S_2O_3 . Calculate the weight of aniline taken.

10.0 g of CaOCl_2 is dissolved in water to make 200 mL solution 20 " mL of " it is acidified with acetic acid and treated with KI solution the I_2 liberated required 40 " mL of " (M)/(20)Na_2S_2O_3 solution. Find the percentage of available chlorine.

10 " mL of " H_2O_2 liberates 12.7 g of iodine form an acidic KI solution. Calculate the normality

0.5g mixture of K_2Cr_2 O_7 and KMnO_4 was treated with excess of KI in acidic medium. Iodine liberated required 150cm^3 of 0.1N solution of thiosulphate solution for titration. Find the percentage of K_2 Cr_2 O_7 in the mixture :

A mixture of FeO and Fe_2 O_3 is completely reacted with 100mL of 0.25M acidified KMnO_4 solution. The resulting solution was then treated with Zn dust which converted Fe^(3+) of the solution to fe^(2+) . The Fe^(2=) required 100mL of 0.10MK_2 Cr_2O_7 solution. Find out the weight % Fe_2O_3 in the mixture.

A sample containing HAsO_(2) (mol. Mass=108) and weighing 3.78 g is dissolved and diluted to 250 mL in a volumetric flask. A 50 mL sample (aliquot) is withdrawn with a pipet and titrated with 25 mL of 0.05 M solution of I_(2) . Calculate the percentage HAsO_(2) in the sample :

A mixture of FeO and Fe_(2)O_(3) is completely reacted with 100 mL of 0.25 M acidified KMnO_(4) solution. The resultant solution was then treated with Zn dust which converted Fe^(3+) of the solution to Fe^(2+) .The Fe^(2+) required 1000 mL of 0.10 MK_(2)Cr_(2)O_(7) solution. Find out the weight % Fe_(2)O_(3) in the mixture.