What is an oxidation-reduction (Redox) reaction and what happens to the oxidation number of oxidized and reduced elements in the reaction?

1. What is an oxidation-reduction (Redox) reaction and what happens to the oxidation number of oxidized and reduced elements in the reaction?
2. What were the objectives of this experiment?
3. How was redox stoichiometry used in interpreting the titration data to achieve the objectives of this experiment?
4. What is a titration? Briefly explain the process and purpose of performing a titration.
5. What information is obtained from the titration process that is important in this experiment?
6. What does it mean to standardize a solution? What is molarity? How is it calculated?
7. How is percent oxalate calculated?
8. What were the chemical and procedural hazards in this experiment and the safety precautions observed to avoid the risk of these hazards?

II. Results Analysis

A. Data and Calculations

Summarize important results and refer the reader to the attached datasheet.

B. Discussion

Part I Standardization of Permanganate Solution—Sodium Oxalate Method
1. What is the purpose of standardizing the potassium permanganate solution and what is the chemical reaction involved? Show the reaction equation.
2. What were the procedural requirements of this section of the experiment?
3. What was the purpose of sulfuric acid in the oxidation-reduction reaction?
4. Why must the titration be carried out between 70 to 90 oC?
5. What were the initial properties of the permanganate solution? Describe any changes or indicators that occurred during the titration? What kind of change has occurred?
6. How was the endpoint of titration determined, and what does the endpoint of titration indicate?
7. What happens at equivalence point and what information was measured that was necessary in the KMnO4 molarity calculations?
8. What was the molarity of the potassium permanganate solution? Show all calculations.
Part II Determination of Oxalate in the Unknown Sample
1. How was percent oxalate ion determined in this experiment? Briefly explain with balanced net-ionic equation.
2. What were the procedural requirements of this section of the experiment?
3. What volume of permanganate solution was required to reach the endpoint of titration?
4. What happens to the reaction at equivalence point?
5. What was the percent by weight of C2O42-in the sample?
6. What was the theoretical percent oxalate in the sample as provided by instructor? What is the percent error? Show all calculations.

III. Conclusions

1. How did you successfully implement the titration data and redox stoichiometry in determining the exact concentration of KMnO4 and percent Oxalate in the unknown sample?

2. Why is titration technique used in potassium permanganate standardization and in the determination of oxalate ion?

3. What does the end point of titration indicate? Briefly explain based on the chemical changes observed and data gathered.

4. How were accuracy and precision achieved in this experiment? How could they be improved in the future?

5. Why are oxidation-reduction titrations important to the study of chemistry? Give an example of a possible application.

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