Relative Reactivities of Metals

well plate with pieces of metal in solution

Last winter I watched a webinar put on by ACS and AACT called "NGSS in the Chemistry Classroom." As a result of watching that webinar, I took an activity that had NGSS Science & Engineering Practices (SEP) integrated into it and tried it out in class. In this activity, students are required to develop their own procedures and data tables. I provided the materials and equipment and only asked that they present their procedure to me before beginning. For some of the students I encouraged to them rethink their procedures to be more efficient (for example, do we need to react Mg with Mg(NO3)2??), whereas for others, I let them be so we'd have a point of discussion after the lab.

This week I had my current Honors Chemistry 1 students work through the lab. Every student was engaged and appropriately challenged. I posted a photo of a student's well plate on Twitter which led to AACT and another Twitter colleague seeking a copy of the lab for others to use a resource. I wanted to share it here in addition to it being available on AACT's website.

Enjoy!

Concepts: 
Collection: 

Safety

General Safety

Please refer to the ACS . Some additional information on these guidelines can be found in a .

Safety resources

: Recognize hazards; Assess the risks of hazards; Minimize the risks of hazards; Prepare for emergencies

 

NGSS

Analyzing data in 9–12 builds on K–8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data.

Summary:

Analyzing data in 9–12 builds on K–8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data. Analyze data using tools, technologies, and/or models (e.g., computational, mathematical) in order to make valid and reliable scientific claims or determine an optimal design solution.

Assessment Boundary:
Clarification:

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories.

Summary:

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories. Construct and revise an explanation based on valid and reliable evidence obtained from a variety of sources (including students’ own investigations, models, theories, simulations, peer review) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.

Assessment Boundary:
Clarification:

Engaging in argument from evidence in 9–12 builds on K–8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about natural and designed worlds. Arguments may also come from current scientific or historical episodes in science.

Summary:

Engaging in argument from evidence in 9–12 builds on K–8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about natural and designed worlds. Arguments may also come from current scientific or historical episodes in science.
Evaluate the claims, evidence, and reasoning behind currently accepted explanations or solutions to determine the merits of arguments.

Assessment Boundary:
Clarification:

Students who demonstrate understanding can construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

*More information about all DCI for HS-PS1 can be found at  and further resources at .

Summary:

Students who demonstrate understanding can construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

Assessment Boundary:

Assessment is limited to chemical reactions involving main group elements and combustion reactions.

Clarification:

Examples of chemical reactions could include the reaction of sodium and chlorine, of carbon and oxygen, or of carbon and hydrogen.

Join the conversation.

Comments 1

Bob Worley's picture
Bob Worley | Sun, 12/20/2015 - 04:11

But what about iron?

Yes I know, you have used nitrates for all the solutions and there is no iron(II) nitrate solution readily available. So just switch to another salt such as iron(II) chloride or sulfate. Unfortunately there are problems again as these salts in solution air oxidise to iron(III). Iron(II) solutions are often made in 1M acid solutions and then other reactions mask the displacement reactions. Grrrr.

So why not start from the solid. As an extensions ask the students to add a few crystals of the iron (II) salt to the well-plate followed by 1 ml of water. When you add a tiny bit of magnesium, the coating of iron appears and with a magnet you can make it follow the field. Other metals can be used in other wellplates.

For a sample of iron, you can use a metal paper clip, cut with snippers or little pins, tack, nails( I sure you have a funny name for them in the States). You can then place iron in the series.

But it is really great to show another way of establishing the activity series.

In a Petri dish, place some filter paper and add drops of 0.1M sodium sulfate to the paper to dampen it. Put the magnesium strip on the paper alongside another metal eg, zinc, copper etc. Use a multimeter to establish the voltage obtain when you press on the metals with the electrodes. Investigate the other metals, keeping magnesium as the reference. You can even add aluminium foil to the series.

I had always done this with copper as the reference (read too many books) with very poor resutls. It was only on changing to Mg as the reference that the order became apparent.

The wonderful world of microchemistry (www.microchemuk.weebly.com )!

Merry Christmas to the chemistry teachers of the USA and Canada or as chemists say “Holmium, Holmium, Holmium.”