Chapter 15, Problem 15.80CQ

Interpretation Introduction

(a)

Interpretation:

The following unbalanced reaction takes place in acidic solution

  ${\text{MnO}}_{\text{4}}{}^{\text{-}}\left(\text{aq}\right){\text{ + Fe}}^{\text{2+}}\left(\text{aq}\right)\to {\text{Mn}}^{\text{2+}}\left(\text{aq}\right){\text{ + Fe}}^{\text{3+}}\left(\text{aq}\right)$

To write the balanced equation

Concept Introduction:

Here are the rules to balance redox reactions in acidic medium:

Determine the oxidation numbers of the elements and write the oxidation and reduction half equation.

Balance the atoms of elements other than O and H. Use H₂O to balance O, H+ to balance H, electrons to balance the charges. Equalize the number of electrons on both the half reactions and then add the half reactions.

Interpretation Introduction

(b)

Interpretation:

The following unbalanced reaction takes place in acidic solution

  ${\text{MnO}}_{\text{4}}{}^{\text{-}}\left(\text{aq}\right){\text{ + Fe}}^{\text{2+}}\left(\text{aq}\right)\to {\text{Mn}}^{\text{2+}}\left(\text{aq}\right){\text{ + Fe}}^{\text{3+}}\left(\text{aq}\right)$

To find how many millilitres of a 0.150 M KMnO₄ solution are needed to react with 25.0 ml of a 0.400 M FeSO₄ solution

Concept Introduction:

  $\text{Molarity = }\frac{\text{moles of solute}}{\text{Liter of solution}}$