The Reactivity Series

Metal Displacement Reactions.

A metal will displace (take the place of) a less reactive metal in a metal salt solution.

Example

iron + copper(II) sulphate iron sulphate + copper.
Fe(s) + CuSO₄(aq) FeSO₄(aq) + Cu(s)

Copper(II) sulphate is blue, iron sulphate is almost colourless (very pale green).

During the displacement, the blue solution loses its colour, and the iron metal is seen to turn pink-brown as the displaced copper becomes deposited on it.

If a less reactive metal is added to a metal salt solution, there will be no reaction - nothing will happen!

iron + magnesium sulphate no reaction.

In these displacement reactions, the metals are competing for the non-metal anion, (in the above examples, (SO₄)^2-).
The order of the metals in the reactivity series can be worked out by using appropriate reactions.

Example

Tin would be seen to displace lead from lead chloride, but would not react with iron chloride.

Therefore, tin must be above lead but below iron.

Experiment

Investigate the relative reactivity of six metals by carrying out displacement reactions

Apparatus and chemicals

All of the usual laboratory glassware

Samples of:

• Magnesium sulphate
• Aluminium sulphate
• Iron II sulphate
• Copper sulphate
• Lead nitrate
• Zinc sulphate
• Magnesium ribbon
• Zinc sheet
• Lead sheet
• Copper sheet
• Aluminium foil
• Iron nails

This is a planning experiment, careful attention should be paid to the variables involved. If any variable cannot be controlled then this must be stated and explained in the evaluation. Anomalous results should be discussed in the conclusion.