1. Metal Displacement Reactions.
A metal will displace(take the place of) a less reactive metal in a metal salt solution.
For example, iron + copper(II)sulfate iron sulfate +copper.
If a less reactive metal is added to a metal salt solution there will be no reaction
iron + magnesium sulfate no reaction.
In these displacement reactions the metals are competing for the non-metal anion. In the above examples the non-metal anion is sulfate - SO42-.

2. The order of the metals in the reactivity series can be worked out by using displacement reactions.
For example, tin would be seen to displace lead from lead chloride but would not react with iron(II) chloride.
tin + lead chloride tin chloride + lead. Sn(s) + PbCl2(aq) SnCl2(aq) + Pb(s)
tin + iron(II) chloride no reaction. Sn(s) + FeCl2(aq) Therefore tin must be above lead but below iron in the reactivity series.
Copper would be seen to displace silver from silver nitrate but would not react with lead nitrate.
copper + silver nitrate copper nitrate + silver. Cu(s) + 2AgNO3(aq) Cu(NO3)2(aq) + 2Ag(s)
copper + lead nitrate no reaction. Cu(s) + Pb(NO3)2(aq) Therefore copper must be above silver but below lead in the reactivity series.

3. Reactivity series
The reactivity series of metals is a tool used to predict products in displacement reactions
The reactivity series is a chart of metals listed in order of declining relative reactivity.

4. The reactivity series of metals is as follows.
Element
Symbol
Group Number
Potassium K 1
Sodium Na
Lithium Li
Calcium Ca 2
Magnesium Mg
Aluminium Al 3
Carbon C
4 (Non-Metal)
Zinc Zn
Transition Metal
Iron Fe
Tin Sn 4
Lead Pb
Hydrogen H
Non-Metal
Copper Cu
Silver Ag
Gold Au
Platinum Pt