Ferris & mona used the orp sensor to titrate a ferrous ammonium sulfate solution, (nh4)2fe(so4)2 with kmno4 titrant.
they titrated a 15.00 ml aliquot of the fe+2 solution with 0.0250 m mno4- solution and determined that the equivalence point was at 20.2 ml.

what is the molarity of the fe+2 solution? 5 fe+2(aq) + mno4-(aq) + 8 h+(aq) â 5 fe+3(aq) + mn+2(aq) + 4 h2oselect one: a. 0.168 mb. 0.0928 mc. 0.0337 md. 0.673 m

The correct option is: A. 0.168 M

Explanation:

Chemical reaction involved:

5 Fe²⁺ (aq) + MnO₄⁻ (aq) + 8 H⁺ (aq) → 5 Fe³⁺ (aq) + Mn²⁺ (aq) + 4 H₂O

Given: For MnO₄⁻ solution-

Number of moles: n₁ = 1, Volume: V₁ = 20.2 mL, Concentration: M₁ = 0.0250 M;

For Fe²⁺ solution:

Number of moles: n₂ = 5, Volume: V₂ = 15 mL, Concentration: M₂ = ?M

To find out the concentration of Fe²⁺ solution (M₂), we use the equation:

Therefore, the concentration or molarity of Fe²⁺ solution: M₂ = 0.168 M