Question

Based on the stoichiometry of the reaction between MnO4- ions and H2O2 in acidic solution, estimate the volume of 0.02 M MnO4- solution required to titrate a 1-mL sample of 3% H2O2.

a) 0.06 mL
b) 0.3 mL
c) 0.6 mL
d) 3 mL

Answer 1

To titrate a 1-mL sample of 3% H2O2 with 0.02 M MnO4- solution, the required volume is 0.06 mL (option a).

Step-by-step explanation:

To determine the volume of 0.02 M MnO4- solution required to titrate a 1-mL sample of 3% H2O2, we need to use stoichiometry. From the balanced chemical equation: 5H2O2 + 2MnO4- + 6H+ → 2Mn2+ + 8H2O + 5O2, we can see that 2 moles of MnO4- react with 5 moles of H2O2.

Now, we can set up a proportion based on the moles of MnO4- and H2O2. Since the sample is 3% H2O2 (by mass), we can calculate the number of moles using its molar mass. Finally, we can use the stoichiometry to find the volume of the MnO4- solution needed.

By solving the proportion, we find that the volume of 0.02 M MnO4- solution required to titrate a 1-mL sample of 3% H2O2 is 0.06 mL (option a).