Hydrogen peroxide solution (20 ml) reacts quantitavely with a solution of KMnO_(4) (20 ml) acidified with dilute H_(2)SO_(4). The same volume of the KMnO_(4) solution is just decolourized by 10 ml of MnSO_(4) in neutral medium simultaneously forming a dark brown precipitate of hydrated MnO_(2). The brown precipitate is dissolved in 10 of 0.2 M sodium oxalate under boiling condition in the presence of dilute H_(2)SO_(4). Write the balanced equations involved in the reactions and calculate the volume strength of H_(2)O_(2).

Hydrogen peroxide solution (20 ml) reacts quantitavely with a solution

1.	Hydrogen peroxide solution (20 ml) reacts quantitavely with a solution of KMnO_(4) (20 ml) acidified with dilute H_(2)SO_(4). The same volume of the KMnO_(4) solution is just decolourized by 10 ml of MnSO_(4) in neutral medium simultaneously forming a dark brown precipitate of hydrated MnO_(2). The brown precipitate is dissolved in 10 of 0.2 M sodium oxalate under boiling condition in the presence of dilute H_(2)SO_(4). Write the balanced equations involved in the reactions and calculate the volume strength of H_(2)O_(2).
Answer» SOLUTION :Meq. Of `MnO_(2) = " Meq. of " Na_(2)C_(2)O_(4)` ` = 10 xx 0.2 xx 2 = 4` ` (C_(2)O_(4)^(2-) to 2CO_(2), ` n- factor = 2) Millimoles of `MnO_(2) = 4/2 = 2` or `2MnO_(4)^(-) + 3Mn^(2+) to 5MnO_(2) `(MOLE ratio is reciprocal of n-factor ratio ) `("Millimoles of " MnO_(4)^(-))/("Millimoles of " MnO_(2))= 2/5` Millimoles of `MnO_(4)^(-) = 2/5 xx ` Millimoles of `MnO_(2)` ` = 2/5 xx 2 = 4/5` `2KMnO_(4) + 5H_(2)O_(2) + 3H_(2)SO_(4) to 2MnSO_(4) + K_(2)SO_(4) + 8H_(2)O + 5O_(2)` ` ("Millimoles of " H_(2)O_(2))/("Millimoles of " MnO_(4)^(-)) = 5/4 ` ` :. ` Millimoles of `H_(2)O_(2) = 5/2 xx 4/5 = 2` `N_(H_(2)O_(2)) xx 20 = 2 xx 2("n- factor for " H_(2)O_(2) = 2) ` `:. N_(H_(2)O_(2)) = 0.2` Volume STRENGTH of `H_(2)O_(2) = 5.6 xx N_(H_(2)O_(2))` ` = 5.6 xx 0.2 = 1.12`