A sample (\( 5.6 \, \text{g} \)) containing iron is completely dissolved in cold dilute HCl to prepare a \( 250 \, \text{mL} \) of solution. Titration of \( 25.0 \, \text{mL} \) of this solution requires \( 12.5 \, \text{mL} \) of \( 0.03 \, \text{M} \) \( \mathrm{KMnO_4} \) solution to reach the end point. Number of moles of \( \mathrm{Fe^{2+}} \) present in \( 250 \, \text{mL} \) solution is \( x \times 10^{-2} \) (consider complete dissolution of \( \mathrm{Fecl_2} \) ). The amount of iron present in the sample is \( y\% \) by weight. (Assume: \( \mathrm{KMnO_4} \) reacts only with \( \mathrm{Fe^{2+}} \) in the solution
Use: Molar mass of iron as \( 56 \, \text{g mol}^{-1} \))
The value of \( y \) is ___________ .
