This classic displacement reaction is a useful experiment to undertake with students. It could equally be done with magnesium turnings and hydrochloric acid or iron and sulfur as long as chemical change is evident.

Allow the students to take iron wool as shown in the video and react it with copper(II) sulfate.

[INSERT CHEM_CI_12_vid]

They should be encouraged to consider the following:

What atoms are present in the wool?

What atoms are present in the copper sulfate?

What do they observe on the surface of the iron wool?

What is happening on the surface of the iron wool? (Ask them to represent this as a cartoon or sketch.)

Is a chemical reaction happening? How do we know?

How can we summarise this chemical reaction?