Redox titrations are used to determine the amounts of oxidizing and reducing age

Question

Redox titrations are used to determine the amounts of oxidizing and reducing agents in solution. For example, a solution of hydrogen peroxide, H2O2, can be titrated against a solution of potassium permanganate, KMnO4. The following equation represents the reaction:

2KMnO4(aq)+H2O2(aq)+3H2SO4(aq)3O2(g)+2MnSO4(aq)+K2SO4(aq)+4H2O(l)

A certain amount of hydrogen peroxide was dissolved in 100. mL of water and then titrated with 1.68 M KMnO4. What mass of H2O2 was dissolved if the titration required 12.3 mL of the KMnO4solution?

Explanation / Answer

moles of KMnO4 = 12.3 x 1.68 /1000 = 0.02066

2KMnO4(aq)+H2O2(aq)+3H2SO4(aq) ----------------> 3O2(g)+2MnSO4(aq)+K2SO4(aq)+4H2O(l)

from the balanced equation :

2 moles of KMnO4 ---------------> 1 mol H2O2

0.02066 moles of KMnO4 -------------> ?? mol H2O2

moles of H2O2 = 0.02066 x 1 / 2

                         = 0.01033

molar mass of H2O2 = 34 g/mol

mass of H2O2 = 0.01033 x 34 = 0.35 g

mass of H2O2 = 0.35 g

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.