Chemistry Lab writing Discussion

Oxidation-Reduction Activity Series – Megan Iott

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.

Data Table: Oxidation-Reduction
	Reactions
Mg in Na2SO4 →	Small amount of bubbles on metal, dark layer dissolved off
Zn in MgSO4 →	Small bubbles on the metal
Pb in Zn(NO3)2 →	Lead changed color to a darker color
Pb in FeCl3 →	Metal turned a dull yellow color
Fe in CuSO4 →	Metal turned a gold copper color, kept dissolving off more metal

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.

Na, Mg, Zn, Fe, Pb, Cu

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)

Iron would be more active than nickel but copper is lower than nickel.

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?

The unknown metal would be higher than iron.

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

Fe is oxidized and Ni is reduced

8. The oxidizing agent and the reducing agent

Fe = reducing agent and Ni = oxidizing agent