Medium INTEGER +4 / -1 PYQ · JEE Mains 2020

The volume, in mL, of 0.02 M K2Cr2O7 solution required to react with 0.288 g of ferrous oxalate in acidic medium is _______.
(Molar mass of Fe = 56 g mol–1)

Answer (integer) 50

Solution

K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub> + FeC<sub>2</sub>O<sub>4</sub> $\to$ Cr<sup>+3</sup> + Fe<sup>+3</sup> + CO<sub>2</sub> <br><br>n<sub>factor</sub> of K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub> = 3 $\times$ 2 = 6 <br><br>n<sub>factor</sub> of FeC<sub>2</sub>O<sub>4</sub> = 1 + 2 = 3 <br><br>m. eq. of K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub> = m. eq. of FeC<sub>2</sub>O<sub>4</sub> <br><br>$\Rightarrow$ ${{6 \times 0.02 \times vol} \over {1000}}$ = ${{0.288} \over {144}} \times 3$ <br><br>$\Rightarrow$ vol = 50 ml

About this question

Subject: Chemistry · Chapter: Redox Reactions · Topic: Oxidation States

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