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A 20 . 0   mL solution containing 0 . 2   g impure H 2 O 2 reacts completely with 0 . 316   g of KMnO 4 in acid solution. The purity of H 2 O 2 (in % ) is______ (mol. wt. of H 2 O 2 = 34 ; mol. wt. of KMnO 4 = 158 )

Correct answer

0

Step-by-step solution

Let mass of pure H 2 O 2 is x gram + 7 MnO 4 −    +    − 1 H 2 O 2 vf = 2     →     + 2 Mn 2 +   +    0 O 2 Eq. of H 2 O 2 = Eq . of MnO 4 - x 34 2 = 0 .316 158   5 x = 0 . 17 So, % purity of H 2 O 2 solution = 0 .17 0 .2 × 100 = 85 %

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