11. Displacement reactions

How do metal elements react with compounds?

Planning

1 Open up a copy of the results sheet (google doc).

2 Choose a colour and underline the four elements.

3 Choose a different colour and underline the four compounds.

4 Fill in the key by your table to show the colours of the elements and compounds.

APPARATUS

  • test tube

  • test tube rack

  • thermometer

  • 4 pieces of copper, iron, zinc, and magnesium

  • solutions of copper sulfate, iron sulfate (irritant), lead nitrate (toxic) and magnesium sulfate

  • eye protection

Method

A Take four test tubes, and fill them about 1/3 full with copper sulphate solution.

B Add a small piece of copper to one tube, iron to the second tube, zinc to the third tube and magnesium to the final tube.

C Leave the tubes for several minutes. Check to see if there is any reaction. Look for:

  • colour changes on the surface of the metal

  • colour changes in the solution

  • bubbles of gas given off

  • a temperature rise

D Write your results in the table.

E Repeat the experiment with the other solutions.

Considering your results/conclusions

1 Add up the total number of reactions for each of the metals and write it in the table.

2 Put the metals in order of reactivity.

3 Add up the total number of reactions for each of the compounds and write it in the table.

4 Put the compounds in order of reactivity.

Can you...

> carry out a safe investigation

> make careful observations

> record results in a clear way

> draw a conclusion and make comparisons

> write a word equation for a reaction