Chemistry Lab writing Discussion
Oxidation-Reduction Activity Series
Peter Jeschofnig, Ph.D.
Version 42-0186-00-01
Lab Report Assistant
This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.
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Data Table: Oxidation-Reduction |
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Reactions |
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Mg in Na2SO4 → |
Bubbles for a few seconds |
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Zn in MgSO4 → |
Small bubbles formed on Zinc |
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Pb in Zn(NO3)2 → |
Changed color of Lead into a darker color |
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Pb in FeCl3 → |
A slight yellow formed on Lead |
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Fe in CuSO4 → |
Changed the Iron into a different color, Red-Orange |
Questions
A. Based on your observations make an activity series of the metals used. List them in such a way that the most active metal is on the left and the least active metal is on the right. Remember, sodium and copper are metals, too.
B. Suppose you inserted a piece of copper into a solution of nickel chloride and observed no reaction. Then if you inserted a piece of iron into the solution of nickel chloride a nickel deposit formed on the bottom of the well in the well plate. Where does nickel fit into your activity series?
The chemical reactions for the preceding question B are: Cu (s) + NiCl2 (aq) à no reaction
Fe (s) + NiCl2 (aq) à 2 Ni (s) + Fe Cl2 (aq)
Ans) The nickel chloride would fit in between aluminum and Iron. The nickel chloride must be more active than copper. Otherwise the copper would replace the nickel in a reaction
C. Suppose you inserted a piece of an unknown metal into a solution of zinc (II) nitrate and observed no reaction. Then if you inserted the unknown piece of the metal into the solution of iron (III) chloride a deposit formed on the bottom of the well in the well plate. Where does the unknown metal fit into your activity series?
Ans) it should go between Iron and Copper because is more reactant than magnesium
For the reaction (Fe (s) + NiCl2 (aq) à 2 Ni (s) + Fe Cl2 (aq) identify:
1. The oxidation number of Ni (s) = 0
2. The oxidation number of Fe in the FeCl2 (aq) = +2
3. The oxidation number of Cl in the FeCl2 (aq) = -1
4. The oxidation number of Fe (s)= 0
5. The oxidation number of Ni in the NiCl2 (aq) = +2
6. The oxidation number of Cl in the NiCl2 (aq) = -1
7. The element that is oxidized and the element that is reduced
Iron is oxidized and Ni reduced
8. The oxidizing agent and the reducing agent
The oxidizing agent what is reduced so Ni (2+) (aq) is the oxidizing agent; the reducing agent is what is oxidized, so Fe(s) is the reducing agent.