State three uses of `KMnO_(4)` and `K_(2)Cr_(2)O_(7)` each.

State what happens when a solid mixture of KCl and K_(2)Cr_(2)O_(7) is heated with conc. Sulphuric acid. Give balanced chemical equation.

Write the preparation of K_(2)MnO_(4) from pyrolusite are (MnO_(2)) . Write the type of magnetism shown by KMnO_(4) and K_(2)MnO_(4) .

(1) MnO_(4)^(-)(aq)+8H^(+)(aq)+5e rarr Mn^(2+)(aq)+4H_(2)O(l), E^(@)=+1.51V (2) Cr_(2)O_7)^(2-)(aq)+14H^(+)+6e rarr 2Cr^(3+)(aq)+7H_(2)O(l), E^(@)=+1.38V (3) Cl_(2)(g)+2e rarr 2Cl^(-)(aq), E^(@)=+1.40V KMnO_(4) and K_(2)Cr_(2)O_(7) both are well known oxidising agent and used in quantitative analysis. If a solution of a reducing agent contains HCl, which one between these two should not be used as an oxidising agent?

V ml solution of Fe^(2+) can be oxidised by 60 ml of KMnO_4 in acidic medium. What will be the volume of K_2Cr_2O_7 required to oxidise V ml of the same Fe^(2+) solution in an acidic medium ? Consider the molarity of KMnO_4 and K_2Cr_2O_7 to be the same.

Which of the following statement(s) is (are) correct when a mixture of NaCl and K_(2)Cr_(2)O_(7) is gently warmed with conc. H_(2)SO_(4) -

State, with equations, what happens when : K_(2)Cr_(2)O_(7) is heated with concentrated HCl.

The amount of iodine that liberates in the reaction of 0.1 mol K_(2)Cr_(2)O_(7) with excess of KI in an acidic solution is -

In volumetric analysis, why is K_(2)Cr_(2)O_(7) used to prepare the standard solution and not Na_(2)Cr_(2)O_(7) ?

The oxidation state of Cr in the product obtained by the reduction of K_(2)Cr_(2)O_(7) by atomic hydrogen is-