Explore BrainMass
Share

Reaction of Hydrogen Peroxide with Potassium Permanganate

This content was STOLEN from BrainMass.com - View the original, and get the already-completed solution here!

1. For the NEW bottle of hydrogen peroxide, record and calculate the following:

(a) Initial burette reading of potassium permanganate used in each titration (mL) and concentration:

(b) The volume of potassium permanganate required to titrate each 10.00 mL portion of the new hydrogen peroxide (mL): (record all three trials' data)

(c) Calculate the number of moles of the H2O2 in the 10.00 mL sample in every titration from the volume of KMnO4 used and the stoichiometry of the reaction.

(d) Take the average of the two closest values you found in step (c).

(e) Use the average from step (d) to calculate the molarity of the H2O2.

(f) Calculate the % by mass (mass) of H2O2 in the original sample. Assume the density is 1.00 g/mL for the NEW H2O2. (MW of H2O2 is 34.01 amu)

2. Repeat the calculations for the OLD bottle of H2O2:

(a) Initial burette reading of potassium permanganate used in each titration (mL) and concentration:

(b) The volume of potassium permanganate required to titrate each 10.00 mL portion of the old hydrogen peroxide (mL):(record all three trials's data)

(c) Calculate the number of moles of the H2O2 in the 10.00 mL sample in every titration from the volume of KMnO4 used and the stoichiometry of the reaction.

(d) Take the average of the two closest values you found in step (c).

(e) Use the average from step (d) to calculate the molarity of the H₂O₂.

(f) Calculate the % by mass of H2O2 in the original sample. Assume the density is 1.00 g/mL for the OLD H2O2.(MW of H2O2 is 34.01 amu)

3. Commercial hydrogen peroxide contains small amounts of organic compounds that are added to stabilize it. If these compounds react with permanganate, how would this affect your results in terms of the % by mass of H2O2?

my data was: KMnO4 added to new peroxide: 20ml to reach the end point
18.1ml
18.05ml
KMnO4 added to old peroxide: 16ml to reach end point
molarity for KMnO4 is .2M 13ml to reach end point
12.65ml to reach end point

the chemical reaction given to use for calculation is:
2[MnO4-]aq + 6[H+]aq + 5[H2O2]aq ---> 5[O2]g + 2[Mn(2+)]aq + 8[H2O]l

© BrainMass Inc. brainmass.com October 25, 2018, 1:08 am ad1c9bdddf
https://brainmass.com/chemistry/organic-reactions/reaction-of-hydrogen-peroxide-with-potassium-permanganate-253798

Solution Summary

Using lab data, this solution explains:

1) How to calculate the number of moles of H2O2 titrated during in a titration using KMnO4.

2) How to use this data to calculate the molarity of the H2O2.

$2.19
See Also This Related BrainMass Solution

Lab: Analysis of Hydrogen Peroxide Solutions

Fill a burette with 50 mL of 0.2M potassium permanganate solution. Add 10 mL of NEW hydrogen peroxide and 2 mL of 6M sulfuric acid to a flask. Titrate the hydrogen peroxide with the KMnO4 solution to the purple endpoint of excess MnO4- ion.

Questions:
(a) Volume of potassium permanganate used in each titration (mL):50mL
(b) The volume of potassium permanganate required to titrate 10 mL of the new hydrogen peroxide (mL):20mL
(c) Calculate the concentration of H2O2 from the volume of KMnO4 used and the stoichiometry of the reaction (MW of H2O2 is 34.01).

In these calculations I got lost.
-I found 0.12655 mol KMnO4. Is this the amount in mol of KMnO4 which reacted? So now how I get the concentration of the H2O2?
-2(C2x0.02L)KMnO4=5(34.01xV1)H2O2. What is C2 and V1?

View Full Posting Details