Selected Redox Reactions
SELECTED REDOX REACTIONS
RESULTS AND DISCUSSION Oxidation-Reduction reaction also known as redox reaction is a process in which there’s a net movement of electrons between reacting species. These types of reactions involve two separate elementary reactions: one that loses electrons and another that gains the electrons that was lost. Gaining of electrons is referred to as Reduction reaction (the species that undergoes reduction is called as oxidizing agent) while losing of electrons is called Oxidation reaction (the reducing agent is the species that undergoes oxidation). In this experiment, seven different set-ups were made which were eventually divided into three different groups. Group 1, those on Part A, were set-ups that investigated the reaction of the permanganate (MnO4-) ion in different media. Group 2, those on Part B, were set-ups that were done in order to study the reaction of Fe(SCN)2+ ion with that of elemental zinc. While the last, Group 3, those on Part C were set-ups that investigated the reaction of Fe4[Fe(CN)6]3 with that of elemental zinc. Group 1, test tubes A to C, vary greatly from each other. This is probably because they differ in the medium used for the reaction to took place. In test tube A, brown precipitate, MnO2, was observed. The reaction was then supported by the equations displayed below:
Test Tube A (Neutral Media)
Reduction Rxn:
2(MnO4- + 4H+ + 3e-) -> (MnO2 + 2H2O)2
Oxidation Rxn:
3(SO32- + H2O) -> (SO42- + 2H+ + 2e-)3
Net Ionic Eq’n:
2MnO4-(aq) + 3SO32-(aq) + 2H+(aq) -> 2MnO2(s) + 3SO42-(aq) + H2O(l)
In test tube B, in which the reaction was done in acidic medium, it was observed that there’s no visible reaction. In this reaction, Mn2+ ion was formed. This ion is colorless and supposedly the solution will turned out to be colorless. It could be that Mn2+ produced was too small that it was not observable at all. This observation was supported by the equations below:
Test Tube B (Acidic Media)
Reduction
RESULTS AND DISCUSSION Oxidation-Reduction reaction also known as redox reaction is a process in which there’s a net movement of electrons between reacting species. These types of reactions involve two separate elementary reactions: one that loses electrons and another that gains the electrons that was lost. Gaining of electrons is referred to as Reduction reaction (the species that undergoes reduction is called as oxidizing agent) while losing of electrons is called Oxidation reaction (the reducing agent is the species that undergoes oxidation). In this experiment, seven different set-ups were made which were eventually divided into three different groups. Group 1, those on Part A, were set-ups that investigated the reaction of the permanganate (MnO4-) ion in different media. Group 2, those on Part B, were set-ups that were done in order to study the reaction of Fe(SCN)2+ ion with that of elemental zinc. While the last, Group 3, those on Part C were set-ups that investigated the reaction of Fe4[Fe(CN)6]3 with that of elemental zinc. Group 1, test tubes A to C, vary greatly from each other. This is probably because they differ in the medium used for the reaction to took place. In test tube A, brown precipitate, MnO2, was observed. The reaction was then supported by the equations displayed below:
Test Tube A (Neutral Media)
Reduction Rxn:
2(MnO4- + 4H+ + 3e-) -> (MnO2 + 2H2O)2
Oxidation Rxn:
3(SO32- + H2O) -> (SO42- + 2H+ + 2e-)3
Net Ionic Eq’n:
2MnO4-(aq) + 3SO32-(aq) + 2H+(aq) -> 2MnO2(s) + 3SO42-(aq) + H2O(l)
In test tube B, in which the reaction was done in acidic medium, it was observed that there’s no visible reaction. In this reaction, Mn2+ ion was formed. This ion is colorless and supposedly the solution will turned out to be colorless. It could be that Mn2+ produced was too small that it was not observable at all. This observation was supported by the equations below:
Test Tube B (Acidic Media)
Reduction
References: Advameg, Inc., 2013. Manganese. In Chemistry Explained: Foundations and Applications. Retrieved March 20, 2013 from, http://www.chemistryexplained.com/elements/L-P/Manganese.html De Vera, G., (n.d.) Selected Redox Reactions. In Scribd. Retrieved March 20, 2013 from, http://www.scribd.com/doc/87950627/Selected-Redox-Reactions-Ppt Petrucci, R.H., Harwood, W.S., Herring, F.G. General Chemistry: Principles and Modern Applications 8th ed. Pearson Education South Asia Pte. Ltd. Singapore 2004 Silberberg, M.S., Chemistry: The Molecular Nature of Matter and Change 5th ed. McGraw-Hill Companies, Inc., New York 2009