JEE Main 2022 · 27 Jul · Shift 1 · Chemistry Q81

ChemistryInteger+4 / -1Question 81 of 90

20 mL of 0.02 M $\mathrm{K_2Cr_2O_7}$ solution is used for the titration of 10 mL of $\mathrm{Fe^{2+}}$ solution in the acidic medium.

The molarity of $\mathrm{Fe^{2+}}$ solution is ______ $\times10^{-2}$ M. (Nearest Integer)

Your answer

Answer and worked solution

Official answer: 24

$\mathrm{Cr_2O_7^{2-}}$ oxidises 6 $\mathrm{Fe^{2+}}$ . $20\times0.02\times6=2.4$ mmol $\mathrm{Fe^{2+}}$ in 10 mL: 0.24 M.

Answer: 24

JEE Main 2022 · 27 Jul · Shift 1, Chemistry question 81