A 2.0 g sample containing MnO 2 is treated with HCl liberating Cl 2. The Cl 2 gas is passed into a solution of KI and 60.0 mL of 0.1 M Na 2 S 2 O 3 is required to titrate the liberated iodine. The percentage of MnO 2 in the sample is (Nearest integer) [Atomic masses (in u) Mn =55 ; Cl =35.5 ; O =16, I =127, Na =23, K =39, S =32]

Question

A 2.0 g sample containing MnO 2 is treated with HCl liberating Cl 2. The Cl 2 gas is passed into a solution of KI and 60.0 mL of 0.1 M Na 2 S 2 O 3 is required to titrate the liberated iodine. The percentage of MnO 2 in the sample is (Nearest integer) [Atomic masses (in u) Mn =55 ; Cl =35.5 ; O =16, I =127, Na =23, K =39, S =32] (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/chemistry/a94faa1a680eba72a58663576278dc51-.png" /> % MnO 2=(3 × 10-3 × 87/2) × 100 =13.05 %

%MnO2​=23×10−3×87​×100 =13.05%

$% M n O_{2} = \frac{3 \times 1 0 ^{- 3} \times 87}{2} \times 100$
$= 13.05%$