Purpose: The technological purpose of this investigation is to test and evaluate the percent concentration of consumer solution of hydrogen peroxide.
Problem:
What is the percent concentration of hydrogen peroxide in a consumer product?
Design:
An acidic solution of primary standard, iron (II) ammonium sulfate-water (1/6), is prepared and the potassium permanganate standard. A 25.0 mL sample of a consumer solution of hydrogen peroxide is diluted to 1.00 L with water (that is, it is diluted by a factor of 40). The standardized potassium permanganate solution is used to titrate the diluted and acidified hydrogen peroxide. The amount concentration of the original hydrogen peroxide is obtained by analysis if the titration evidence, and by using the graph.
Procedure:
Calculate the required mass of FeSO4 * (NH4)2SO4 * 6H2O(s) to prepare 100.0 mL of a 0.0500 mol/L solution.
FeSO4 * (NH4)2SO4 * 6H2O(s) M= 392.21 g/mol C v = n (0.0500 mol/L) * (0.100 L) = 0.005 mol n M= m (0.005 mol) * (392.21 g/mol) = 1.96 g
1) Measured the required mass of iron (II) compound in 100 mL beaker
2) Dissolve the solid in about 40 mL of H2SO4 (aq)
3) Transfer this solution into a clean 100 mL volumetric flask, rinsing the beaker solution into the volumetric flask to get to 100 mL of solution.
4) Pipette 10.0 mL of the standard iron (II) solution into a 250 mL Erlenmeyer flask.
5) Titrate the acidic iron (II) sample with KMnO4 (aq).
6) Repeat steps 4 and 5 until three consistent results are obtained within 0.1 mL.
7) Pipette 10.0 mL of H2O2 (aq) solution into a clean 250 mL Erlenmeyer flask.
8) Measure out 5.0 mL of H2SO4 (aq) solution and add it to the 10 mL H2O2 (aq) solution.
9) Titrate the acidic H2O2 (aq) solution with KMnO4 (aq).
10) Repeat steps 7-9 until three consistent results are obtained within 0.1 mL.
11) Dispose of solutions into waste buckets.
Materials:
Lab Apron - Biuret
Eye Protection - Graduated Cylinder
100