Question

o Estimated Concentration of Diluted Peroxide: . Remember when we had a 1:1 ratio we wanted the concentrations of NaOH and HCl to be similar. So if NaOH was 0.025 M then we would want HCl to be 0.025 M. In this case, we have a 5:2 ratio so if the concentration of KMnO4 is approximately 0.025M then we need to multiple by (5/2) to get the concentration we want to have of peroxide. o Volume (L) diluted peroxide à Volume (L) KMnO4 • Gives Estimated volume of diluted peroxide (erylenmeyer flask) • Gives Estimated volume of KMn04 (endpoint) • Volume of KMnO4 range (15-25 mL) and Volume of Peroxide range (10 - 25 mL). • Why do we need to dilute peroxide? • Why do we want to predict the volume in the erylenmeyer flask and the endpoint prior to doing the titration?

hydrogen peroxide titration, concentration of KMnO4 is 0.025 and the concentration of H2O2 from the mol ratio is 0.882 M

Answer 1

If we use a concentrated solution then we will need only small volume to reach the endpoint of titration so it increases volume error.other reason is that when concentrated solution is added local surplus of H2O2 and the generated mno2 will dissociate H2O2 and increase volume error .By predicting endpoint and volume we can look whether calculation is right or not .if calculation is correct and we get the same in experiment we can use this calculation for various concentrations . Without wasting time by doing titration